Sarah, I really like this recipe. It is from a book called "Thin for Life"
by Anne M. Fletcher.

Blueberry Yogurt Muffins

2 cups all-purpose flour
1 T. baking powder
1/2 t. salt
1 cup fresh or frozen blueberries
4 egg whites, at room temperature
1 1/2 cups plain nonfat yogurt, at room temperature
1/2 cup granulated sugar plus 3 t. for sprinkling
over tops
1 t. vanilla

1. Preheat oven to 400 degrees.( I bake them at 375)
2. Sift together flour, baking powder, and salt. ( I don't sift)
The recipe says to add the blueberries now and stir lightly to coat,
but because I use the frozen, I add them at the end.
3. Beat the egg whites at high speed with an electric mixer until they
hold soft peaks. Add yogurt, 1/2 cup sugar and vanilla. Mix for 30 to
40 seconds until combined. Add liquid mixture to dry ingredients and
fold together just until flour is moistened.( this is where I add my
frozen blueberries, making sure not to mix to much or the batter
will turn sort of purplish) Batter should not be smooth. Do not overmix.
4. In a nonstick 12-cup muffin pan, divide batter evenly between the cups
Sprinkle 1/4 t. sugar evenly over each muffin. Bake for 20 minutes or
until tops are golden. Remove from the tins and allow to cool.

I add some grated lemon or orange rind to these also. I have a couple more
recipes for you I will post.