Step 1

Preheat oven to 425°F and line a 12-cup standard muffin pan with baking cups; spray baking cups lightly with cooking spray. For the crumb topping, combine brown sugar, flour, cinnamon, and salt in a small bowl; add melted butter and vanilla, and toss mixture with a fork until crumbly. Chill topping in the freezer until needed.

Step 2

Whisk together flour, sugar, baking powder, baking soda, and salt in a large bowl; make a well in the center of the mixture. Combine mashed banana, yogurt, melted butter, egg, and vanilla in a medium bowl; add to flour mixture and fold in just until incorporated.

Step 3

Fill each baking cup 3/4 full of batter and sprinkle evenly with crumb topping. Place muffin pan in the oven and bake for 5 minutes at 425°F. Reduce temperature to 350°F and continue baking 10 to 12 minutes (for a total baking time of 15 to 17 minutes), until muffins are golden and a toothpick inserted in the center comes out clean or with a few crumbs attached. Let muffins cool in pan on a wire rack for 5 minutes before removing from pan to cool.

Step 4

For the glaze, whisk together powdered sugar, salt, vanilla bean paste, and milk in a small bowl. Drizzle glaze over muffins and let set before serving.