Broccoli Cauliflower Soup
Broccoli Cauliflower Soup is a creamy, comforting bowl that blends tender broccoli and cauliflower with savory notes of onion and sharp cheddar. Easy weeknight dinner friendly and freezer safe, it balances richness and bright mustard tang for a satisfying, healthy meal you will want to make again and again.
Equipment
- Large Pot
- Immersion Blender
- Ladle
Ingredients
- 2 tablespoons extra virgin olive oil Enhance flavor and prevent sticking by coating the pan with a fruity, peppery oil ideal for sautéeing aromatics at medium heat.
- 2 tablespoons unsalted butter Enrich the soup with a creamy, savory fat that helps develop a silky mouthfeel when melted and combined with flour for a roux.
- 1 medium yellow onion chopped Add a sweet, aromatic base by softening until translucent to build depth and natural sweetness in the soup.
- 2 large carrots peeled and chopped into 1/4- to 1/2-inch dice Introduce earthy sweetness and body by cooking until tender, contributing texture and natural sugars to balance the broth.
- 2 cloves garlic minced Provide pungent, savory brightness by gently cooking to release aromatic oils that lift the overall flavor profile.
- 1 teaspoon kosher salt Season the pot and enhance natural flavors by evenly distributing savory salinity to taste throughout the soup.
- 1/4 teaspoon freshly ground black pepper Contribute subtle heat and depth by adding freshly cracked spice that sharpens the flavor without overpowering.
- 1/2 teaspoon dried thyme Add warm, herbal notes that complement the vegetables and provide a gentle savory backdrop to the broth.
- 1/4 cup white whole wheat flour or all-purpose flour or gluten free flour Thicken and bind liquids by creating a light roux that yields body and a smooth consistency when cooked with fat.
- 3 cups low sodium chicken stock Build a savory, aromatic liquid base and add depth while keeping sodium controlled to allow other flavors to shine.
- 1 1/2 cups nonfat milk for a richer soup, use whole milk Lighten the broth with a creamy, dairy element that softens acidity and adds a gentle richness to the soup.
- 1 medium head broccoli chopped into small florets Provide tender vegetable texture and a fresh, slightly bitter green flavor when cut into small florets and simmered.
- 1 medium head cauliflower chopped into small florets Contribute a sweet, nutty vegetable component with a firm bite that mellows when cooked, adding bulk and balance.
- 1 teaspoon Dijon mustard Introduce tangy, sharp acidity that brightens the overall flavor and helps cut through the richness of the soup.
- 1 cup shredded sharp or extra sharp cheddar cheese plus additional for serving Add pronounced sharpness and creamy melting texture when stirred in, contributing a rich cheesy umami finish.
- 1/4 cup nutritional yeast or finely grated Parmesan I love the nutritional yeast for its extra health benefits. You can also omit this and add an additional 1/2 cup shredded cheddar instead. Offer nutty, savory umami boost and optional extra cheesiness or a dairy-free alternative to enhance depth.
Instructions
- In a large pot, heat the oil and butter over medium-low heat until the butter melts. Add the onion and cook until it is very brown and soft, about 8 minutes (this develops big flavor so be patient). Increase the heat to medium. Add the carrots, and cook for 3 minutes, stirring occasionally. Stir in the garlic, salt, pepper, and thyme. Sprinkle the flour over the vegetables and mix to combine.: The kitchen should begin to smell warm and buttery, with a faint fruity note from the extra virgin olive oil . Gently heating these fats creates a soft sheen in the pot, and you want the butter to melt without bubbling aggressively, which would indicate too high heat. This low temperature helps the onion soften rather than brown too quickly, and it sets the stage for even cooking. If the fats start smoking, reduce the heat and wipe the pan clean if there is browning, because burned fat will taint the entire soup.
- Cook until the flour disappears, about 2 minutes. Slowly stir in the broth. Add the milk, broccoli and cauliflower. Bring to a simmer. Place a lid over the pot, leaving it partially uncovered, and let simmer until the broccoli and cauliflower are tender, about 15 minutes, stirring occasionally.: As the onion cooks, it will shift from opaque to translucent, then to a warm golden brown; the aroma becomes sweet and savory. This caramelization builds depth that carries through the whole soup, so resist the urge to rush by cranking heat. Stir occasionally so the pieces brown evenly and do not stick. A common mistake is stirring too little, which causes uneven charring, or stirring too aggressively, which prevents color development.
- Stir in the Dijon. With an immersion blender puree the soup until it is thick and creamy but still has some texture to it. (Alternatively, you can ladle a few scoops into a blender and puree a few batches. Be careful not to fill your blender more than halfway, as hot liquids like to splatter). Stir in the cheese. Continue stirring until the cheese is melted and the soup is creamy, 2 to 3 minutes. Taste the soup and season with additional salt and pepper to taste. Ladle the chowder into bowls, and serve warm, sprinkled with additional cheddar as desired.: You will notice the pot's surface shimmer slightly as the temperature rises, which helps the next vegetables to sizzle gently. This step preps the pan for the carrot , giving it a quick sear that brightens its sweetness. If you skip raising the heat, the carrot may steam instead of developing a touch of caramelization, resulting in a blander note.
- Add the carrots and cook for 3 minutes stirring occasionally: The carrot should hit the warm fat and release a faint toasted sweetness, making a soft sizzling sound. Cooking for a few minutes softens the edges and concentrates flavor, but leaves enough structure so they do not disintegrate. If you overcrowd the pot, the vegetables will steam and not brown, so give them room to sizzle.
- Stir in the garlic, salt, pepper, and thyme: Aromas will rise as the minced garlic warms, delivering a fragrant note that complements the sweet onion and carrot . The kosher salt helps draw moisture and intensify flavors, and thyme adds an earthy lift. Add these seasonings now so they bloom in the fat. Burning the garlic is the most likely error here, so stir continually and keep the heat moderate.
- Sprinkle the flour over the vegetables and mix to combine: The mixture will take on a lightly dusted look as the flour coats the softened vegetables. This step begins building body for the soup, and as the flour cooks it loses any raw starchy taste. Ensure all bits are coated, scraping up any fond from the pot. If you do not cook the flour enough, the soup can taste pasty and raw.
- Cook until the flour disappears about 2 minutes: You will see the roux become smoother and take on a faintly nutty scent as it cooks, which indicates the raw edge is gone. Small bubbling across the surface is normal. Stir constantly so it does not brown; too much color here can muddy the final flavor. Undercooking is common, so wait the full time.
- Slowly stir in the broth: As you add the chicken stock in a slow stream, the mixture will loosen and the pot will hiss softly, turning from thick paste to a liquid with suspended vegetables. Stirring while adding prevents lumps and ensures a silky base. If you dump the stock in all at once, you risk clumps forming and an uneven texture.
- Add the milk broccoli and cauliflower: The surface will cool slightly when the milk is added, then warm again as you bring the soup back toward simmer. The chopped broccoli and cauliflower will float and bob, their colors deepening as they soften. These vegetables are the body of the soup, so cut them to similar sizes for even tenderness. If pieces vary too much, some will overcook while others remain firm.
- Bring to a simmer place a lid over the pot leaving it partially uncovered and let simmer until the broccoli and cauliflower are tender about 15 minutes stirring occasionally: The pot should maintain a gentle simmer with small bubbles breaking the surface, not a rolling boil. The aroma will turn vegetal and warm, and when pierced with a fork the florets should be tender but not collapsing. Leaving the lid partially off allows steam to escape and concentrates flavor without losing too much moisture. Overcooking will make the vegetables mushy and dull the color.
- Stir in the Dijon: Adding the Dijon mustard at this stage brightens the soup and layers a subtle tang. It cuts through the richness and rounds the dairy notes, elevating the overall balance. Mix until incorporated, and taste to see how it lifts the flavors. Using too much will introduce an assertive mustard note.
- With an immersion blender puree the soup until it is thick and creamy but still has some texture to it: As you puree, the sound softens to a steady whir and the soup transforms visually from chunky to a velvety body with small flecks of vegetable. Leaving some texture preserves mouthfeel and interest. If using a countertop blender, work in small batches and vent carefully to avoid splatter. Overblending can make the soup gluey.
- Stir in the cheese: Off heat, fold in the shredded cheddar and watch it melt into a glossy, savory finish. The soup will thicken slightly and take on a warm golden hue. Adding cheese slowly prevents separation; if the soup is too hot it can cause the cheese to become grainy. If that happens, remove from heat and stir in a small splash of milk to smooth it.
- Continue stirring until the cheese is melted and the soup is creamy 2 to 3 minutes taste the soup and season with additional salt and pepper to taste ladle the chowder into bowls and serve warm sprinkled with additional cheddar as desired: The final minutes are about harmony, sensing a silky texture and balanced seasoning. The aroma of melted cheese and vegetables should be comforting, and a final taste will tell you if it needs a pinch more kosher salt or black pepper . Serve warm, and add extra shredded cheddar on top for a melty garnish. A common oversight is skipping the final tasting, which can leave the soup under seasoned.
Notes
- Storage: Store leftovers in an airtight container in the refrigerator for up to four days, making sure to cool the soup to near room temperature first to protect texture and flavor.
- Reheating: Gently rewarm the soup in a Dutch oven over medium low heat, stirring frequently to prevent sticking and to reincorporate any separated liquids for a smooth finish.
- Freezing: Freeze in airtight, freezer safe containers for up to three months, leaving a bit of headspace for expansion, and thaw overnight in the refrigerator before reheating to maintain texture.
- To make vegan: Use almond milk and a vegan butter substitute, omit the cheddar, use nutritional yeast instead of Parmesan, and add one tablespoon freshly squeezed lemon juice with the almond milk to brighten flavors.
- Flour options: Substitute with gluten free flour if needed, but allow it to cook a little longer in the fat to remove any raw taste and ensure a smooth body.
- Cheese choice: Sharp or extra sharp cheddar gives the best savory lift, but adjust quantity if you prefer milder dairy notes, adding slowly until the balance feels right.