Preheat the oven to 350 degrees F.

Grease the muffin tins and set aside.

In a medium bowl, cream together the butter and the sugars until light and fluffy. Stir in the eggs and milk and combine.

In a separate bowl, combine the flour, baking powder, baking soda and salt.

Slowly stir the dry ingredients into the wet ingredients and stir until just combined.

Add the oatmeal and stir.

Place 1 tablespoon of the cookie dough into each of the muffin tins.

Top the cookie dough with 1/2 of the Snickers bar.

Cover the Snickers bar with another tablespoon of cookie dough.

Bake for 8-10 minutes.

Remove from the oven and allow the muffins to rest in the tins for 5 minutes.

Run a knife around each muffin to loosen them from the sides.

Carefully remove each muffin and place on a cooling rack.