1/2cupunsalted butter, softened to room temperature
1/2cuplight brown sugar
2large eggs, at room temperature
1 3/4cupsall-purpose flour
For the glaze:
Preheat the oven to 425 degrees F. Spray a jumbo muffin pan with nonstick spray.
To make the crumb topping:
In a medium bowl combine sugars, cinnamon and melted butter. Using a rubber spatula, stir in the flour until thick and crumbly. Set aside.
To make the muffins:
In the bowl of an electric mixer fitted with the paddle attachment, beat the butter on high speed until smooth, about 1 minute. Add the brown sugar and sugar and beat on high until fluffy, about 2 minutes. Add the eggs, yogurt, and vanilla, scrapping down the sides of the bowl as needed. Beat on medium speed for 1 minute, then increase speed to high and beat until the mixture is combined.
In a large bowl, mix together flour, baking soda, baking powder, cinnamon, and salt. Add dry ingredients into the wet ingredients and mix until combined. Add the milk, mixing until combined and no lumps remain. Using a rubber spatula, fold in the peaches and blueberries.
Divide the batter evenly among the muffin tins, filling each cup all the way up to the top. Divide the crumb topping among each of the muffin cups, crumbling with your hands to make some big chunks.
Bake for 5 minutes at 425 degrees then lower the temperature to 350 degrees and bake for an additional 23 to 25 minutes or until a toothpick inserted in the center comes out clean. Remove from oven and cool.
To make the glaze:
Whisk the confectioners' sugar, milk and vanilla extract together. Drizzle over muffins. Store in a sealed container for up to 2 days.
*You may bake these muffins in a standard size muffin tin. Reduce baking time to 20 minutes; 5 initial minutes at 425 degrees F and 15 minutes at 350 degrees F.