Brown the butter

• Melt the butter in a saucepan over medium heat and cook until golden brown and nutty.
• Pour into a bowl and let cool slightly.

Make the cookie dough

• Whisk the brown sugar and white sugar into the browned butter.
• Beat in the egg until smooth.
• Stir in the flour and baking soda until a soft dough forms.

Stuff with Nutella

• Flatten a portion of dough in your hand and place a spoonful of chilled Nutella in the centre.
• Seal the dough around the Nutella and roll into a ball.
• Repeat with the remaining dough and Nutella and place on a baking tray.

Chill the dough

• Chill the stuffed cookie balls so they hold their shape.

Bake

• Bake in a preheated oven at 180 °C until the edges are set and the centres still soft.
• Let cool on the tray for a few minutes before serving.