Blend: Blend all ingredients except coconut oil in a food processor until relatively smooth. Slowly drizzle in oil, stopping when you reach a thick paste that is no longer dry (it's ok if it is a little gritty).
Chill: Spread into a parchment-lined baking pan (should be about 1 inch thick). Optionally top with chopped nuts or chocolate. Chill in the freezer until firm, about 15 minutes.
Serve: Cut into blocks and serve. Store leftovers in an airtight container in the fridge.