Firstly, preheat the oven to 180C/160C Fan/Gas Mark 4. Then grease a 9x9inch square baking tin, and line the base and two opposite sides with baking paper.
For the browned butter: Place the butter into a small saucepan over a medium-high heat and melt stirring every now and then. Keep the melted butter on the heat as it foams, stirring every now and then until the foaming subsides and you're left with a light brown butter with darker flecks. Then take off the heat and pour into a large heat-proof bowl.
For the dough: Firstly, chop the chocolate into rough chunks and set aside. Then add both the sugars into the browned butter bowl and using an electric hand-whisk, whisk on a high speed until well combined. Then add the egg, egg yolk and vanilla and whisk again until well combined. Then whisk in the flour, baking powder, bicarbonate of soda and table salt until you have a soft thick dough. Finally, mix in the chopped chocolate.
Tip the cookie dough into the prepared baking tin, and press down evenly with a spoon or spatula. Then press the mini eggs and malteser bunnys into the cookie dough. Place into the oven and bake for 20 minutes until lightly golden brown, then remove from the oven and leave in the tin for 15 minutes. Finally, remove from the tin and leave to cool completely on a cooling rack. Then slice into 8 bars or 16 squares.
Easter cookie bars will keep in an air-tight container for 2-3 days.
Keyword cookie bar, cookies, dark chocolate, easter