Make the Streusel: Add the flour, brown sugar, granulated sugar, cinnamon, and salt to a bowl.

Scatter the butter across the top and rub butter into the flour mixture.

Whisk together flour, baking powder, baking soda, and salt.

Whisk together sugar, eggs, lemon zest and juice, and vanilla.

Add the butter and whisk until combined.

Stir in the dry ingredients in 3 additions, alternating with the buttermilk. Fold in the chopped peaches.

Fill the liners or muffin cup ¾ of the way full and sprinkle a generous pinch of the streusel topping across the tops of the muffins.

Bake for about 18 minutes. Set aside to cool on a cooling rack for 10 minutes.

Drizzle vanilla glaze over the top of the muffins with a spoon and allow the glaze to set. Serve and enjoy!