Guinness and Onion Tart Recipe

Preheat oven to 375°F.

Roll out the pie crust and fit it into a 9-inch tart pan.

Prick the bottom with a fork and set aside.

In a large skillet, melt the butter over medium heat.

Add the onions and sauté until golden brown for about 15-20 minutes.

Add Guinness, mustard, salt, and black pepper and stir to combine.

Cook for another 5-10 minutes until the liquid has evaporated.

Add the cheese to the onion mixture and stir until melted.

Pour the mixture into the prepared crust and spread evenly.

Brush the beaten egg over the crust edge and bake for 20-25 minutes or until golden brown.