Crumb topping: In a medium bowl, combine both sugars, the cinnamon, and melted butter. Using a rubber spatula, stir in the flour. The crumb topping will be thick and crumbly. Set aside.

Preheat oven to 425°F. Spray muffin pan with nonstick spray.

Make the muffins: In a medium bowl using a handheld mixer, beat butter on high speed until smooth and creamy, about 1 min.

Add brown sugar & granulated sugar and beat on high until creamed, about 2 mins. Add eggs, yogurt, and vanilla extract.

Beat on medium speed for 1 min, then turn up to high speed until the mixture is combined.

In a large bowl, toss together the flour, baking soda, baking powder, cinnamon, and salt. Pour the wet ingredients into the dry ingredients and slowly mix with a whisk.

Add the milk, gently whisking until combined and little lumps remain. Fold in apples.

Spoon the muffin batter evenly between all 6 muffin tins.

Press a handful of the crumb topping into the top of each.

Bake for 5 mins at 425°F, then keeping the muffins in the oven, lower the oven temperature to 350°F and bake for 18 minutes.

Make the glaze: whisk all of the ingredients together and drizzle over warm muffins.