1. Preheat oven to 350 degrees Fahrenheit (175 degrees Celsius).
2. In a large mixing bowl, beat the margarine or oil, sugar, vanilla, and eggs; lower speed and add cocoa, flour, baking powder, and salt, beating until well combined.
3. Spread batter onto a parchment-lined cookie sheet and bake for 30 minutes. Remove from oven and allow to cool. Spread caramel cream over the cooled crust and sprinkle with 1/2 cup of chopped nuts. Place in freezer.