Preheat the oven to 350° F.

Grease two 9-inch round cake pans with non-stick spray. Set aside.

In a large mixing bowl, whisk together brownie mix, egg, water, and oil until smooth.

Divide the batter evenly into the prepared cake pans and smooth with a rubber spatula.

Bake for 18-20 minutes, or until the edges are slightly crispy. Be careful not to underbake the brownies, or they will fall apart when assembling the ice cream cake,

Allow the brownies to cool in the cake pans for approximately 15 minutes before carefully removing them from the pans and placing them on a wire cooling rack to cool completely.

Prepare the ice cream while the brownies are cooling.

Pour the heavy whipping cream and vanilla extract into the bowl of a stand mixer and beat for about 2 minutes, or until stiff peaks form when the beater is lifted. (Pro Tip: To make whipped cream faster, chill your mixer bowl and electric whisk attachments in the freezer for 30 minutes beforehand. The whipped cream whips up faster!)

Add the sweetened condensed milk to the mixing bowl and mix gently with a rubber spatula until fully incorporated.

Add the sprinkles and mix gently until fully incorporated.

Pour the ice cream into an 8x4 inch loaf pan and smooth with a rubber spatula.

Spoon dollops of caramel over the top of the ice cream and swirl it throughout the ice cream with a butter knife. You can use as much or as little caramel as desired.

Freeze the ice cream for about 2-4 hours, or until it’s the consistency of soft-serve ice cream.

Remove the ice cream from the freezer and assemble the ice cream cake.

Place one of the brownie rounds into the bottom of a 9" springform pan, spread the ice cream evenly over the top, and finish with the second brownie round.

Place the cake in the freezer overnight.

Remove the cake from the freezer approximately 10 minutes before serving and remove the sides of the springform from the cake, leaving the cake on the base of the pan.

Top with swirls of whipped cream and extra sprinkles. Keep any leftover cake in the freezer.