Sour cream muffins with poppy seed streusel

I came across this recipe last night and realized I had all the ingredients on hand. So this morning James and I made them since we had a lazy snow day today. They were also the perfect thing to deliver to our neighbors for shoveling our driveway. :)
James and Todd gave them 2 thumbs up! Todd asked, "When can you make these again?" I subbed yogurt for the sour cream and I bet you could use lemon rind rather than orange and that would be good too!


Sour cream muffins with poppy seed streusel, by Cooking Light
Ingredients
Streusel:
3 tablespoons sugar
2 tablespoons all-purpose flour
1 tablespoon butter, melted
1 teaspoon poppy seeds
Muffins:
2 cups all-purpose flour
3/4 cup sugar
2 teaspoons baking powder
1 teaspoon baking soda
1/2 teaspoon salt
3/4 cup fat-free buttermilk
1/4 cup butter, melted
1 tablespoon grated orange rind
1 teaspoon vanilla extract
1 large egg, lightly beaten
1 (8-ounce) container reduced-fat sour cream
Cooking spray
Preparation
Preheat oven to 375°.

To prepare streusel, combine first 4 ingredients in a small bowl; set aside.

To prepare muffins, lightly spoon 2 cups flour into dry measuring cups; level with a knife. Combine 2 cups flour, 3/4 cup sugar, baking powder, baking soda, and salt in a medium bowl, stirring with a whisk. Make a well in center of mixture. Combine buttermilk and remaining ingredients except cooking spray in a small bowl; add to flour mixture, stirring just until moist. Spoon batter into 15 muffin cups coated with cooking spray. Sprinkle streusel evenly over batter. Bake at 375° for 18 minutes or until golden brown. Remove muffins from pans immediately; place on a wire rack.