Mix cacao powder, almond flour and ½ cup of the walnuts in a food processor until the mixture resembles a course flour.
Then add the rest of ingredients except the walnuts. If your dates are hard, soak them in hot water before adding them to the mixture.
After all ingredients come together in a ball and are moist, add the leftover ¼ cup walnuts and pulse so that you have chunks of walnuts in the brownies.
Oil a baking dish with coconut oil, then spread the brownie mixture into the baking dish. Put in the refrigerator while you mix the frosting.
Chocolate Frosting
Mix all ingredients except walnuts until smooth and creamy. Use food processor if necessary.
Spread frosting on brownies. Sprinkle chopped walnuts on top, pressing them into the frosting. Refrigerate.
Notes
Store in the refrigerator so that frosting doesn't melt.These no-bake brownies will last about a week in an airtight container in the fridge.