Preheat your oven to 180C/350F and line a baking tin with greaseproof paper.
Place the butter and sugar in a double boiler on medium heat until the butter is beginning to melt.
Whisk to combine and help the sugar and butter mix evenly, continue whisking to help dissolve the sugar for at least 1 minute.
Remove from the heat and allow to cool for 2 minutes.
Add in one egg and whisk until well combined, repeat with the remaining egg until the mixture is smooth.
Whisk in flour, salt and cocoa powder until the brownie batter is combined and smooth.
Set aside a handful of the mini eggs and toss ¾ of the eggs into your brownie batter, stirring to combine.
Pour into prepared baking tin and smooth out.
Scatter the mini eggs over the top of the batter and bake for 30 minutes and you can smell it wafting from your oven.
Remove and allow to cool.
Slice.
Best served with a glass of milk.