• To make the brownies, preheat the oven to 350 degrees and grease an 8 x 8 inch baking dish. In a medium sized sauce pot, melt the butter. Remove from heat and whisk in sugars until mixture is smooth and creamy. Add the eggs and egg yolk, one at a time, whisking well after each addition. Stir in vanilla.
• Stir in the cocoa powder and flour until just combined. Stir in chocolate chips. Bake for 40-45 minutes or until center is set and toothpick inserted in the center of the brownies comes out with just a few moist crumbs. Allow to cool.

To assemble the cake:

• You will need about 2/3 of the pan of the brownies. I think you can figure out what to do with the leftovers. Take out 2/3 of the brownies and crumble or cut them into small bite sized pieces.
• In a bowl, mix together the sprinkles and ice cream until well distributed. Spread half of the ice cream in the bottom of a 9 inch loaf pan. Top the ice cream with an even layer of the crumbled brownies. Follow that with the other half of the ice cream and a final layer of the brownies. Cover the pan with saran wrap and freeze for at least 4 hours or overnight.
• When ready to serve, drop the bottom of the pan in 2-3 inches of hot water to loosen it up, then turn it over onto a serving platter. Slice and serve, allowing guests to top the slices with their favorite sauces and ice cream toppings.