When you want to double a recipe there is no single rule about doubling all the ingredients, but here are some guidelines:
- Spicy ingredients like chiles and cayenne pepper rarely need to be doubled. Start slow by adding one-fourth more than in the original recipe–you can always increase the heat, but it is very hard to fix a dish that is too spicy.
- When searing or sautéing, use the amount of oil or butter it takes to cover your pan's surface.
- When doubling a recipe, start by using 1 1/2 times the dried herbs and spices and salt. Again, you always add more, but you can't take it away.
For more tips on doubling recipes for baked goods, see the post about doubling and tripling ingredients for cakes, cookies, and muffins.