Apple Streusal Muffins

I found this recipe in a great cookbook I have and decided to try it out. It turned out great and they were a big hit!

2 C all-purpose flour
1 C sugar
1 T baking powder
1-1/4 t cinnamon
1/2 t salt
1/2 t baking soda
2 large eggs, beaten
1 C dairy sour cream
1/4 C butter, melted
1 C finely diced apples, unpeeled

STREUSEL TOPPING
1/4 C sugar
3 T all-purpose flour
1/4 t cinnamon
2 T butter

In large bowl, stir together flour, sugar, baking powder, cinnamon, salt, and baking soda; set aside. In small bowl, beat eggs, sour cream, and butter. Add all at once to dry ingredients along with apples. Stir just until moistened. Fill well-greased muffin tins two-thirds full. Combine topping ingredients (I left the butter soft but not melted); sprinkle on top of muffins. Bake at 400* for 20-25 minutes. (It may just be my oven, but my first batch was severely burned at about 18 minutes. I cut the time down and started checking them around 12 minutes) Yield: 18 muffins.