1. Preheat the oven to 350°F (180°C). Line a 9×13 inches (23x33cm) baking pan with baking parchment and set aside. Chop the chocolate and add together with 1/4 cup (30g) of the cocoa powder to a large heatproof bowl. Set aside.

2. Add the butter to a saucepan and melt. Let bubble and cook for a moment, then remove from the heat and let sit until there are no more bubbles coming up, then add to the bowl with the chocolate and mix until you get a smooth chocolate sauce. Set aside to cool down a bit.

3. Add the eggs, both of the sugars, vanilla extract, and salt to a large bowl and mix until light and fluffy – takes about 10 minutes. Add the cooled chocolate sauce and mix in. Mix the flour with the remaining cocoa powder (1/2 cup/60g) and sift into the bowl – gently fold in until just combined. Pour the batter into the prepared baking tin and bake for about 20 minutes, then take out of the oven and drop the pan one or two times on your counter to get some air bubbles out – just a bit, you don’t have to smash the half baked brownies completely :P Return to the oven for another 20-24 minutes until the edges are set. Test with a wooden skewer in the center of the brownies – there can be some batter sticking to the skewer but it should not be liquid anymore. Take out of the oven and let cool down completely on a wire rack.

4. For the buttercream add the room temperature (!) butter to a large bowl and mix on high speed for about 5 minutes until very light and fluffy. Add the vanilla extract and salt and mix in. While still mixing, gradually add the sweetened condensed milk – do this very slowly or the buttercream might curdle. Continue mixing until you get a nice and fluffy buttercream. Divide between several small bowls and color with food colors. Cut the brownies to size – if they are a bit domed on the sides you can level that out too. Cover the brownies with a layer of buttercream and then decorate to your liking.