Place the frozen beetroot into a microwave container with ½ cup of water and cook on high for 8 minutes. Drain and allow to cool.
Heat the chocolate in a bowl of a double boiler and then allow it to cool.
Preheat the oven to 180C / 350F and line +-16 -18 muffin cups with cupcake paper liners.
Process the beetroot in a food processor with the sunflower oil until a smooth consistency (there might still be a few very small chunks), about 3 – 4 minutes.
Separate the eggs and using an electric mixer, whip the whites until stiff peaks. Remove from the bowl and set aside. In the same mixing bowl, add the egg yolks, sugars, beetroot and oil mixture, vanilla, salt, chocolate, and almond flour, and mix until well combined for about a minute.
Sift the flour, cocoa powder, and baking powder and add them to the wet batter and briefly mix until incorporated.
By hand, gently fold through the whisked egg whites.
Using a medium ice cream scoop, fill the lined muffin cups with batter ensuring it comes ¾ of the way up the liner. Bake for 23 – 25 minutes and until springy to the touch and baked through. Cool on a cooling rack and then remove to further cool out of the tins. Once the cupcakes are fully cooled, make the buttercream frosting.
Make the icing sugar by melting the chocolate in a double boiler and then allowing it to cool to room temperature.
Whip all the other ingredients together for a few minutes until fluffy.
Ice the cupcakes and decorate them with chocolate shavings, walnuts, or anything you like. Give these cupcakes an Easter theme top with colourful mini eggs.