Preheat the oven to 350°F.: As the oven warms you will notice a faint hum and gentle heat filling the kitchen, which helps create an even bake. Getting the oven precisely to 350°F ensures the biscuits cook through without over browning, producing a tender center and a lightly firm exterior. If the oven is cooler than expected the biscuits may become dense, so use an oven thermometer if you doubt your appliance. A common mistake is skipping preheating, which can make baking times unreliable and affect texture.
Open the canned biscuits, cut each biscuit into quarters, and place them into a bowl.: The aroma of the raw biscuit dough is slightly sweet and yeasty, and cutting them into quarters increases surface area so they absorb sauce and cheese evenly. Using clean hands or a spatula, separate pieces gently to avoid compressing them, which can lead to dense pockets. If pieces stick together in the can, pull them apart carefully to preserve layers. A mistake here is overhandling the dough, which compresses air pockets and reduces fluffiness.
Pour the spaghetti sauce over the biscuits, add Italian seasoning, and stir well.: Stirring introduces the tangy scent of spaghetti sauce and releases fragrant herbal notes from the Italian seasoning . The sauce should coat each biscuit piece so they absorb flavor as they bake, without becoming soggy. Use a gentle folding motion to coat evenly, and stop once all pieces look glazed. Over saturating causes soggy centers, while undercoating yields dry bites, so aim for an even sheen on all pieces.
Add 3/4 of the pepperoni (reserve the remaining 1/4) and 1/2 of the cheese to the bowl, and stir well.: When you fold in most of the pepperoni and half the mozzarella cheese , the mixture starts to smell savory and rich. The cheese will begin to cling to the sauced dough, promising gooeyness after baking. Reserving some toppings for the surface creates a contrast of textures. Avoid overmixing which can break down the biscuit pieces too much, making the final texture homogeneous instead of pull apart.
Pour the mixture into a greased 9×13 pan.: As you mound the sauced pieces into the prepared pan you will see pockets of sauce and cheese nestling between dough pieces. Greasing the pan prevents sticking and encourages a golden base. Spread the mixture evenly so baking is uniform, and press lightly to create an even top. A common error is using an ungreased pan which can cause the loaf to cling and tear when served.
Sprinkle the remaining pepperoni and cheese on top before placing the pizza into the oven. If using any of the optional toppings, sprinkle them on too.: The act of topping adds visual appeal, and you will see the surface take on a mosaic of meat and cheese. This final layer crisps and browns, giving pleasing contrasts to the softer interior. If you add black olive slices , chopped green bell pepper , or chopped onion , scatter them evenly to avoid soggy pockets. Overcrowding the top can prevent proper browning.
Bake for approximately 25 minutes, or until the biscuits are fully cooked. They will be slightly firm when you press down on them.: During baking the kitchen fills with a toasty, herbal aroma, and you will see bubbling around the edges where sauce and cheese meet. The sound is mostly quiet, but you may notice gentle sizzling as moisture evaporates. The visual cue is golden edges and melted cheese, and the tactile test is pressing lightly to feel slight firmness. If they are still soft and doughy, bake a few minutes longer. A typical mistake is pulling it out too soon which yields undercooked centers.