The only real difference between muffins and other quick breads is the pan you bake them in. But those little muffin cups allow for a lot more potential variation, depending on what you do at the last minute before baking.
Anything goes when it comes to varying this master recipe. See the variations below for more ways to spike the recipe.From How to Cook Everything (Completely Revised 10th Anniversary Edition)
Muffins, Infinite Ways
Makes: 12 medium or 8 large muffins
Time: About 40 minutes
3 tablespoons melted butter or neutral oil, like grapeseed or corn, plus more for the muffin tin
2 cups all-purpose flour
1/4 cup sugar, or to taste
1/2 teaspoon salt
3 teaspoons baking powder
1 cup milk, plus more if needed
1. Heat the oven to 375°F. Grease a 12-cup muffin tin and line it with paper or foil muffin cups if you like.
2. Mix together the dry ingredients in a bowl. Beat together the egg, milk, and melted butter or oil in another bowl. MakeRead More »from Mark Bittman: Muffins, Infinite Ways