Preheat oven to 350 degrees

Fill your muffin pan with muffin liners. Sit to the side.

In a small bowl combine brown sugar and cinnamon. Sit to the side.

Using a mixer, combine butter and sugar until completely combined.

Add eggs to the bowl and mix until everything is fully combined.

Slowly add in flour in 3 increments. (Add 1/3 of flour then mix. Repeat 2 more times)

Pour milk into bowl and mix until batter is creamy.

Mix diced apples into the brown sugar and cinnamon mixture.

Using a piping bag, add about 1tbs of batter to each muffin cup. 

Add about a tbs of the apple mixture.

Top the muffin cups with more batter.

Top each muffin cup with about a tbs of the apple mixture and extra brown sugar and cinnamon.

Bake for 20-25 minutes or until each cupcake is done in the middle using a toothpick test.

Let muffins cool.

To make the glaze, just mix your powdered sugar and milk. 

Drizzle desired amount on top of each muffin.