Preheat the oven to 180°C (standard oven)

Grease quiche dish

Lay pre-rolled pastry in dish & push in to the edges. Leave the pastry overhanging the dish and prick the base with a fork

Put pastry in the oven to cook for approx 15 minutes

Meanwhile put oil in a pan & add onions until softened

Add bacon lardons & cook until slightly golden

Add mushrooms & cook until softened

Leave mixture to cool

Remove pastry from oven

Once mixture is cool, drain off any excess liquid

In a separate bowl, mix the eggs, milk, salt & pepper together

Add bacon mixture on to the pastry and add the 40g of cheese

Pour in egg mix

Scatter 20g of cheese on top of egg mix

Bake in the oven for 25 minutes 

Remove, cut and eat immediately or leave to cool and eat cold at a later date