How to Scale a Recipe Without Ruining the Result

Divide the number of servings you want by the number the recipe makes. That number, the scaling factor, is what you multiply every ingredient by.

Scaling often produces amounts you can't measure easily, such as 0.375 cup or 2.67 tablespoons. Convert them to the next smaller unit:

The ingredients scale simply. What doesn't scale in a straight line is the cooking.

Evaporation depends on the surface area of the pot, not how much is in it. Double a stew in the same pot, or one only slightly wider, and the liquid evaporates at about the same rate, so the doubled stew ends up thinner if you cook it for the original time. Give it longer, use a wider pot, or start with a little less liquid and add more if needed.

Bigger pots also take longer to come to a simmer, and big batches of rice or grains can cook unevenly. Stir more often and check for doneness rather than following the clock exactly.

Salt and strong spices such as cayenne, cloves, and nutmeg are easy to overdo in a large batch, especially in anything that reduces. A practical approach many cooks use: add about three-quarters of the scaled amount, then taste near the end and add the rest if needed. You can always add more; you can't take it out.

Wine reductions take longer in a deep pot than in a wide pan, too. Let the wine simmer until it smells mellow rather than sharp before you add stock or cream.

A doubled recipe doesn't need a hotter oven or twice the time. Oven temperature controls how fast the outside browns compared with how fast the inside sets. Raise it and the outside burns before the middle is done.

The most reliable way to double a cake or quick bread is to bake it in two pans of the original size. Then the batter depth is the same and the bake time stays about the same. If you use one larger, deeper pan, expect it to take noticeably longer, and consider lowering the oven by about 25°F (15°C) so the edges don't over-bake.

Leaveners (baking powder and soda) scale fine at the usual 2× or 3×. Problems with doubled cakes almost always come from a pan that's too deep, not from the leavening amount.

A large egg weighs about 50 g out of the shell. To use part of one, beat it with a fork and measure by weight: half an egg is about 25 g, a third about 17 g. If the scaled amount is close to a whole egg (say 1.8 eggs), rounding to 2 is usually fine in cakes and cookies.

Yeast in a large bread dough can ferment faster because big doughs hold warmth. Watch the dough rather than the clock, or use slightly less yeast for a longer rise.