Oreogasm Skillet Brownie

Preheat oven to 350 degrees F. In a large cast-iron or oven-proof skillet, pour half brownie batter and spread to cover bottom of pan. Add a layer of Oreos and top with remaining brownie batter. Dollop spoonfuls of vanilla frosting and, using a toothpick, drag the tip through the frosting and batter to create swirl. Top with half the crushed Oreos and bake until cooked through and a toothpick comes out with only a few moist crumbs, 22 to 24 minutes. Let cool 10 minutes, then top with vanilla ice cream, hot fudge, and remaining crushed Oreos. Serve immediately (preferably with spoons).