Pour half the water in two half-gallon pitchers. Sprinkle 4 ounces ground coffee over the water in both pitchers. Cover and let sit 30 minutes. After 30 minutes, stir.: As the mixture sits you will notice the grounds slowly wetting and darkening, releasing a layer of coffee aroma that is fragrant but not scorched. The first 30 minutes encourages initial saturation so flavors can begin to extract evenly, and the gentle stir helps all the grounds contact water . A common mistake is to aggressively agitate, which can encourage gritty particles to stay suspended. If you see too many fines floating, let them settle for a few minutes before covering again.
Cover again and let sit at room temperature overnight.: Overnight steeping is where the brew develops its smooth character, and you should detect a calmer, sweeter scent compared to hot brewed coffee. The slow extraction reduces acidity and brings out chocolatey undertones from the dark roast coffee grounds . Avoid placing the pitchers in direct sunlight or near heat, which can accelerate unwanted flavors. If your kitchen is warm, aim for a cooler corner to keep the profile balanced.
Line a fine mesh strainer with a double layer of fine cheesecloth or a coffee filter set over a large bowl or pitcher. Pour the coffee mixture through the strainer and allow the liquid to run through. The coffee mixture will take several minutes to strain, and will need to be done about 2 cups at a time. When finished, discard the coffee grounds.: During straining you will hear a slow, steady drip and see a clear, deep brown liquid collect. This step clarifies the brew by removing grounds and fines, which improves mouthfeel and storage life. Work in manageable batches to avoid overflowing and be patient, because rushing leads to cloudy results. If the flow is extremely slow, lift and re fold the cheesecloth to redistribute the grounds, then continue straining.
Pour the strained coffee in a covered container in the fridge until cooled.: Chilling the brew not only makes it ready for iced drinks, it also helps flavors settle and mellow further. You should notice the aroma tightening into sweeter notes as it cools, and keeping it covered prevents it from picking up fridge odors. A common oversight is leaving it uncovered, which can dull the flavor; always store cold brew in a sealed container for best longevity.
In a pitcher or bowl whisk together the heavy cream and sweetened condensed milk. Store in the fridge in an airtight container until ready for use.: Whisking these together creates a smooth, homogeneous creamer that blends easily into cold liquids. The mixture should be glossy and viscous, with a sweet aromatic scent. If your creamer is lumpy, whisk longer or strain it through a fine sieve. Avoid adding plain granulated sugar directly to cold liquid, because it may not dissolve, instead integrate it into the creamer if you need extra sweetness.
Fill a glass with ice (or better yet, coffee ice!). Pour 3/4 full with coffee. Fill the remaining 1/4 with the creamer mixture. If you prefer a sweeter and creamier iced coffee you can do equal parts instead.: The immediate sensory reward here is the bright brown swirl when the creamer hits the cold coffee, and the aroma of roasted coffee lifting from the glass. Coffee ice cubes maintain strength as they melt, avoiding dilution. A tip to avoid over sweetening is to taste before adding the full amount of creamer, then adjust. Watch for separation; give a quick stir to combine fully.
Add in optional add-ins if desired.: This is where you personalize the cup with sauces, syrups, or a dusting of ground cinnamon . The aromas will bloom and the surface may gain a glossy sheen from caramel or chocolate syrup. Add small amounts and taste incrementally, because syrup and sauce can quickly overpower the coffee. If your drink becomes too sweet, add more cold brew to rebalance.