The ingredient math is easy; here's how to get seasoning, pans and timing right too.
Cooking for a crowd is the most common reason to scale a recipe, and it’s where a straight multiply-by-two can quietly go wrong. The ingredient math is the easy part; seasoning, pans and timing are where big batches trip people up.
Flour, sugar, liquids, fats and proteins all scale in a straight line. If a recipe calls for 1½ cups of flour, doubling needs 3 cups. Weighing in grams makes big batches far more reliable than scooping, because small scooping errors multiply too.
Salt, spices, garlic and chili often don’t need full multiplication. A doubled pot of chili with exactly double the cayenne can come out noticeably hotter, because flavors concentrate as a larger volume reduces. Add about 1.5× the seasoning when you double, taste near the end, and bring it up only if needed. Leavening is the opposite trap: baking soda and powder do scale, but measure precisely because they’re potent.
A doubled tray of vegetables piled onto one sheet steams instead of roasting — spread across two pans. An overfull pot is slow to heat and prone to boiling over. For baking, don’t just pour a double batch into one deep pan; bake two, or choose a wider pan of similar depth.
Doubling the ingredients doesn’t double the cooking time. What changes time is depth and thickness, not total volume — two thin trays baked side by side finish close to the original. Big batches do take longer to reach temperature, so lean on a thermometer rather than the clock.
Set your target servings in the Recipe Scaler and it multiplies every ingredient and flags the ones — salt, leavening — worth a second look.