Created by Mepps on January 27, 2014
Step 1: Preheat the oven to 375°.
Step 2: For the topping - in a medium bowl, combine all the topping ingredients together. Rub with your fingers to form coarse crumbs. Refrigerate until ready to use.
Step 3: For the muffins - butter a 12-cup muffin pan.
Step 4: In a medium bowl, whisk the 1 1/2 cups of flour with the baking powder, baking soda, salt, cinnamon and lemon zest.
Step 5: In a large bowl, using a handheld mixer, beat the egg at medium speed until frothy. Add the sugar and melted butter, beat until pale yellow, 1 minute. Beat in the sour cream and vanilla until blended. Using a spatula gently mix in the dry ingredients almost blended.
Step 6: In a bowl, toss the blueberries with 1 tablespoon of flour. Using a spatula, fold the blueberries into the batter.
Step 7: Fill the muffin cups three-fourths full of batter and sprinkle with the topping. Bake for 25 minutes, or until a cake tester inserted in the center of a muffin comes out clean.
Step 8: Remove the muffins from the pan and let cool on a rack.