Fat can make food rich, but it's best to avoid fats where they're not needed. A great trick to make richer pasta sauce, soups, and stews is to use mushroom broth.

1. Buy some dried mushrooms; this is a great chance to get something to supplement the button mushrooms you usually use.
2. Soak the dried mushrooms in warm water for 15 minutes. Drain and reserve the water.
3. Place the mushrooms in boiling water for 10 minutes. Drain and reserve the water
4. Both of the waters should be thick and brown and, if you taste them, very mushroom-y. Combine the water.
5. Bring the combined water to a boil and reduce by about 1/4. This is a strong and tasty mushroom broth. (You can reduce more if you have time and don't mind a thicker liquid in what you're cooking.)
6. Add to your sauce, soup, or stew. Be moderate unless you want the mushroom flavor in your food.
7. Freeze what you don't use.
8. Make sure to use the dried mushrooms! They won't last. If you don't want to use them in your dish, try cutting them up and mixing them with rice, then stuffing the combination in a pepper and baking it.