Apple Snickerdoodle Muffins

Preheat oven to 425 degrees. Line muffin cups with paper liners, see note**.For the muffin topping:In a small mixing bowl whisk together sugar, flour, and 2 tsp cinnamon. Add butter and stir until combined, set aside.For the muffins:In a medium mixing bowl whisk together flour, baking powder, 1 tsp cinnamon, nutmeg and salt for 20 seconds, set aside. In a separate medium mixing bowl toss together apples with 1/4 cup of the brown sugar, and remaining 1 tsp cinnamon, set aside.In a large mixing bowl, using an electric hand mixer, beat together oil, granulated sugar and remaining 1/2 cup brown sugar until blended. Add in eggs, sour cream and vanilla and mix until combined. Add flour mixture to oil mixture and mix just until nearly combined then pour apple mixture over top and fold with a spatula just until evenly distributed. Divide batter among prepared muffin cups**. Crumble up topping into small bits and sprinkle evenly over muffins. Bake in preheated oven 5 minutes then reduce oven temperature to 375 and continue to bake 11 - 16 minutes longer until toothpick inserted into center comes out clean (larger muffins will take more near greater amount of time). Transfer to a wire rack and allow to cool 10 minutes.For the glaze:In a small mixing bowl whisk together powdered sugar and milk. Drizzle over muffins and allow glaze to set. Store muffins in an airtight container.*To measure flour, first whisk flour in container for a few seconds to fluff it up a little then scoop with a measuring cup and sweep top with a butter knife to level. For best results just use a kitchen scale :).**I like tall muffin tops so I filled 12 muffin cups heaped full, but to get regular size muffins you can fill 18 muffins cups about 3/4 full. Original recipe lists 18.Recipe source: from The I Heart Naptime Cookbook by Jamielyn Nye