Optional: Caramel sundae sauce, extra cookies, mini chocolate chips
PREP: Line a 9x13-inch pan with parchment paper and lightly spray with nonstick spray. Preheat the oven according to the brownie mix instructions.
BROWNIEBASE: Follow package directions to prepare the brownies. Spread the brownie batter into the prepared 9x13-inch pan and spread evenly. Bake according to package directions, removing 2-3 minutes earlier than indicated by the instructions.
HOT FUDGE: Remove and allow to cool to room temperature. Cover and place in the freezer for 30 minutes. Warm hot fudge in the microwave for 15-20 seconds for easier spreading, and then top the brownies evenly with the hot fudge topping.
COOKIES: Coarsely chop all but three of the cookies and gently press the cookie pieces on top of the fudge topping. Cover and freeze for 10 minutes.
ICE CREAM: Scoop the ice cream on top of the cookie pieces (don't let the ice cream melt too much or it will get icy upon being re-frozen). Using a spatula, gently press and spread the ice cream as evenly as possible; then cover and return to the freezer until very firm -- at least 3 hours. I like freezing them overnight.
FINISHING: Before serving, smooth the thawed whipped topping over the bars and crush the remaining three cookies. Sprinkle those crumbs over the bars along with miniature chocolate chips if desired.
SERVE: Let bars sit out for 5-10 minutes before cutting into them.For cleaner (and easier) slicing, run your knife under hot water and then wipe off with a towel between slices. Top individual bars with caramel sundae sauce if desired.
Note 1: Brownies: I use and recommend Betty Crocker’s® Supreme Triple Chunk Brownie Mix (21 ounces) for these bars.Leftovers: Whipped topping and crushed cookies are best added to the servings you are enjoying -- these additions don't re-freeze as well; they become a bit icy. Make sure to cover bars very tightly before re-freezing.