Leek, Goat Cheese and Thyme Sheet-Pan Tart

• 1 roll of ready-rolled puff pastry (about 270 g)
• 2 medium leeks (about 500 g)
• 1 tablespoon olive oil, for the leek
• 100 g crème fraîche
• 1 teaspoon Dijon mustard
• 150 g soft goat cheese
• 1 tablespoon fresh thyme leaves
• 1 egg
• Salt and black pepper
• 100 g mixed green salad leaves
• 1 small firm apple
• 1 tablespoon apple cider vinegar
• 1 tablespoon olive oil, for the dressing

How to make it

1. 1

   Preheat the oven to 220 °C (200 °C fan). Line a baking sheet with parchment paper.

2. 2

   Cut the leek into thin rings and rinse them thoroughly. Heat 1 tablespoon olive oil in a frying pan. Cook the leek with a pinch of salt over medium-low heat for 7–9 minutes, until soft but not browned. Stir occasionally, then leave it to steam dry for a little while.

3. 3

   Unroll the puff pastry, keeping it on its parchment paper, onto the baking sheet. Using a knife, score a border about 2 cm from the edge without cutting all the way through. Prick the center all over with a fork. Bake the pastry for 8 minutes.

4. 4

   Stir the crème fraîche and Dijon mustard together and season with black pepper. Remove the baking sheet from the oven. Gently press down any air bubbles in the center, then spread the crème fraîche mixture over it, inside the scored border.

5. 5

   Spread the leek over the base. Crumble the goat cheese on top and sprinkle with the thyme leaves. Beat the egg and brush it only over the pastry border.

6. 6

   Bake the sheet-pan tart for 18–20 minutes, until golden brown and cooked through. Check after 15 minutes: if the edge is browning quickly, lower the oven temperature slightly. Let the tart rest for 5 minutes before slicing.

7. 7

   Meanwhile, prepare the salad. Wash and dry the salad leaves. Cut the apple into thin wedges. Whisk the apple cider vinegar with the remaining tablespoon of olive oil and a pinch of salt to make a dressing. Toss with the salad and apple just before serving.

8. 8

   Cut the warm sheet-pan tart into four pieces and serve with the salad.