Preheat the oven to 180C /160C fan. Line the base and sides of a 20cm (8 inch) square tin with greaseproof paper. Make sure the paper sticks out 2.5cm (about an inch) above the edge of the tin.
Add the brownie mix to a bowl. Melt the butter (or dairy free alternative) and pour this over the brownie mix and stir until the mix is starting to form a batter. Lightly beat the eggs, add to the mix and stir together well. Spread the batter into the tin and smooth the top.
Chop your Creme Eggs in half, and lay them out on top of the brownie mixture. We’ve used normal-sized Creme Eggs here, but feel free to use mini ones if you would prefer. Bake for 18-22 minutes.
When they’re done, leave them to cool in the tin for 20 minutes before lifting out and transferring to a cooling rack. Use the paper to help you. Leave to cool completely before slicing.
