Tarte aux oignons caramélisés et au gruyère

Ingrédients

• 320 g shortcrust pastry
• 3 onions (large, sliced)
• 60 g butter
• 200 ml double cream (heavy cream)
• 3 eggs (large)
• 100 g gruyere cheese (grated)
• 25 g Parmesan (grated)
• 3 sprigs fresh thyme

Préparation

1. 1

   Heat the oven to 190C/375F. Unpack the pastry sheet and line a 23 cm (9-inch) tart tin.

2. 2

   Place the pastry sheet in the lined tin and fill the tart with baking beans. Blind bake for 15 minutes. Remove the beans and paper and bake for another 10 minutes.

3. 3

   Meanwhile, melt the butter in a frying pan over medium heat and add the sliced onions. Turn the heat to low and cook for 20-25 minutes until caramelized. Stir from time to time to make sure the onions caramelize evenly.

4. 4

   In a medium bowl, mix the eggs, double cream (heavy cream), gruyère, and chopped thyme. Season with salt and pepper.

5. 5

   Stir the onions into the egg mix and pour everything into the tart case.

6. 6

   Sprinkle the parmesan on top and cook for 25 minutes or until set and golden brown.

7. 7

   Allow the tart to cool for five minutes before cutting into slices.