Interesting that you come to a business school forum looking for cooking advice. I'm not sure what you mean by "American" food, since it's a pretty broad label. What restaurants describe as American cuisine tends to be heavily influenced by French, Italian and other European styles, sometimes with a little bit of Asian or Latin American influence thrown in. Or it could mean southern food, or BBQ, or hamburgers and hot dogs, or mac n' cheese, or you get the idea.
A good place to start would be websites like cooks.com or epicurious.com, both of which have a pretty good selection of recipes. And probably the best advice would be next time to admit to your friends that you don't know how to cook.
Get the best GMAT Prep Resources with GMAT Club Premium Membership