Add the vanilla extract and sugars to a bowl, whisking to combine. Then add each egg one by one, whisking lightly between each egg. Whisk in the melted chocolate.
Add flour mixture to wet ingredients, folding in gently using a silicone spatula until all dry ingredients are fully combined and no clumps or traces of flour remain.
Gently press 6-10 mini creme eggs down into the batter. Bake the brownies for 30-35 minutes until a toothpick comes out of the center clean and there is no wobble in the batter if you jiggle the pan.