First, line a “deep dish” style, freezer safe ceramic bowl with plastic wrap. Make it about 4 inches too long on either side.
Next, with your protein ice cream of choice in the ice cream maker (Vanilla: Blend 3 cups almond milk, vanilla flavor, with 3 scoops Vanilla Prograde Protein powder or any other protein powder, then add in the ice cream maker), take 1/2 - 3/4 of a cup of frozen berries of your choice (raspberries, strawberries, blueberries), food process them until broken down and small, and press to the bottom of the dish.
Put it in the freezer while you’re waiting for the ice cream to finish.
Take 1/2 cup of nuts of your choice (walnuts, pecans, almonds) and food process until pieces are small and uniform. When the vanilla ice cream is ready, spoon carefully and top the chilled berry topping, then finish with the layer of nuts. This will be the crust, when the cake is flipped upside down. Freeze till solid.
Cut ice cream into four equal servings and serve.