Mushroom Béarnaise tart

1. Set the oven to 185 degrees.

2. Put the rapeseed oil, shallot and garlic into a frying pan and cook over a gentle heat for a couple of minutes without colouring. Then add the mushrooms and the vinegar and turn up the heat a little. Cook for two minutes or so, until the mushrooms start to soften, then add the cream.

3. Let the cream bubble and reduce until it forms a thick sauce around the mushrooms, then remove from the heat, allow to cool and add the tarragon, egg yolk, salt and pepper.

4. Unfurl the pastry. Keep the parchment and put it on a baking tray, then lay the pastry on top.

5. Brush lightly with egg wash, then spread the mushroom mixture over the pastry, leaving a 3cm rim all around.

6. Fold the edge in on itself to form a crust, then brush with egg wash.

7. Bake in the oven for 25 minutes until golden. Eat warm with a green salad.