Mixing Muffin Batter

Follow instructions in your recipe. Most muffins are mixed using the following method:

Mix the dry ingredients in one bowl with a whisk or fork to thoroughly distribute all ingredients completely.
Combine the liquid (wet) ingredients in another bowl. Mix thoroughly.
Add liquid ingredients to dry ingredients all at once.
Using a wooden spoon, mix just until the dry ingredients are moistened, 15 to 20 light strokes. There should be some small lumps.
Chopped nuts, fruit and other small "add in" ingredients may be combined with the dry ingredients or folded gently into the batter near the end of mixing.
Realize that overmixing can cause muffins to be tough, bake unevenly, create elongated holes (or tunnels) and/or form peaked tops.