Preheat the oven to 350˚F (180˚C). Grease 2 8-inch (20 cm) round cake pans with nonstick spray.
2. Step
In a large bowl, combine the melted ice cream, cake mix, and egg whites. Whisk until smooth.
3. Step
Divide the cake batter evenly between the prepared pans. Bake according to the package instructions, about 30 minutes, or until a toothpick inserted in the center of the cakes comes out clean. Let cool completely, about 30 minutes.
4. Step
Place 1 cake on a cake stand or platter. Spread an even layer of frosting over the cake. Top with the other cake layer. Spread a thin layer of frosting over the top and sides of the cake.
5. Step
Chill the cake in the refrigerator for 15 minutes.
6. Step
Use the remaining frosting to coat the top and sides of the cake. Place the cake over a baking sheet to catch any excess cookies. Use your hand to coat the sides of the cake with crushed mint cookies.
