Preheat the oven to 350 and prepare an 8X8 inch baking pan with cooking spray and parchment paper. Make sure you have enough excess parchment paper on the sides of the pan to be able to lift the brownies out of the pan to cool.
In a bowl, add hot butter, oil, and sugar. Using a hand mixer, or a stand mixer fixed with the paddle attachment, beat the butter-sugar mixture for 2 mins. Don't rush this step. This creates the shiny top to the brownie.
Add eggs and vanilla to the butter-sugar mixture. Beat again for 2 minutes or until pale and creamy.
In the same bowl, sift in the cocoa, flour, salt, crushed mini eggs, and shaved chocolate. Fold mixture together. Be careful not to over mix.
Pour batter into the 8X8 baking pan, sprinkle with salt, and place in the oven for 20-23 minutes. You want the center to be set, but still fudgy.
Let the brownie cool fully. Option to place brownie on a cooling rack to speed up the process. While the brownie is cooling, kick on with the buttercream icing.
Add butter, cocoa, icing sugar, vanilla, and cream to a bowl. Using a hand mixer or a stand mixer fixed with the paddle attachment, mix the icing together. It may seem dry at the beginning but keep going. Beat on high for 2 minutes.
Once the brownie is fully cooled spread on icing, and then sprinkle on the crushed mini eggs. I found using the side of a knife or the bottom of a cup is the best way to crush the mini eggs. Be sure to get a mixture of finely crushed and coarsely crush mini eggs. The texture is key.
Sprinkle with salt. DO NOT SKIP THIS STEP. Chocolate gets even better with salt.
Take a moment to really enjoy these brownies. These are a once-in-a-while treat, so really just give yourself permission to enjoy. These are insanely good. You deserve it.
