Turn the oven on to warm up at 180°C and prepare a 20cm round pan (or 8'' x 8'' square pan) with some parchment paper at the bottom of it.

Microwave and melt the butter, then add the sugar and microwave it in 30 seconds intervals. Mix the sugar and butter well until the sugar is fully dissolved.

Let the sugar and butter mixture cool slightly, then add the eggs one at a time and combine.

Once all the eggs are incorporated, add the cocoa powder, salt and vanilla and fold in.

Fold in the flour and pour into the tin of your choice.

Bake for 35 minutes and let it cool completely before decorating.

Once you are ready to decorate, cut the round brownie into 8 slices, then set them aside.

Using your standing mixer or hand mixer, beat the cold butter cubes for 3-5 minutes, making sure you scrape the bowl down every so often. It needs to look light in colour and increased in volume.

Now add the icing sugar, starting with 200g, and mix on low speed until it's fully incorporated. You might need to keep adding more icing sugar until you reach your desired consistency, but make sure you add the cream and vanilla before you do so.

Add the colouring and reach your desired shade of green, then transfer to a piping bag fitted with the piping nozzle of your choice and decorate each brownie slice. Add the sprinkles and serve them.