In a large mixing bowl, beat brown sugar, sugar, and butter until fluffy.

Add egg, milk, and vanilla, beating until combined.

In a medium bowl, whisk together flour, baking soda, and salt.

Add to mixing bowl gradually, beating until combined.

Fold in chocolate chunks, mini chips, and M&M’S® Caramel.

Spray a 10-inch cast-iron skillet with non-stick spray.

Spread the batter into the skillet.

Bake at 325 for 40-45 minutes, or until edges are golden and a toothpick inserted near the center comes out clean. You may have to poke it in a few places to make sure it's set in the center, since there's a lot of chocolate and chips in the cookie.

Cool for 20 minutes. Cut into slices.

Serve warm with ice cream, chocolate sauce, and caramel sauce.