Bacon & Spring Onion Tart

Serves 4

This tart uses both the bulb and tops of the spring onions, but you can use scallions or white onions. If you prefer, substitute ricotta for the creme fraiche and another hard cheese for the Gruyère. The tart is best the same day it’s made.

1 sheet all-butter puff pastry (about 9¾ inches by 10½ inches), thawed

2 large egg yolks

8 ounces sliced thick-cut bacon, cut crosswise into ¾-inch pieces

2 cups thinly sliced spring onions, bulbs thinly sliced, green tops thinly sliced on the diagonal

1 teaspoon fresh thyme leaves Kosher salt and freshly ground black pepper

1/3 cup creme fraiche

1 tablespoon finely chopped fresh chives

1 cup grated Gruyère or Comté cheese

Instructions: Preheat the oven to 400 degrees. Unroll the thawed sheet of puff pastry onto a sheet of parchment paper or a silicone pan liner set on a rimmed baking sheet. With the tip of a sharp knife, score a ½-inch border around the edge of the pastry, taking care not to cut all the way through. Beat together one egg yolk and 1 teaspoon water in a small bowl. Brush the egg wash on the border, then transfer the dough (still on the pan) to the freezer.

Heat a medium frying pan over medium heat. Line a plate with paper towels and set nearby. Add the bacon to the pan and cook, stirring, until the fat has rendered and the bacon is becoming crisp, 3 to 5 minutes. With a slotted spoon, transfer the bacon to the paper towel-lined plate. Pour the bacon fat into a heatproof bowl, then measure out 3 tablespoons of the fat and return it to the frying pan (if you don’t have enough bacon fat, add olive oil to make up the difference). Return the pan to medium and add the onions and a fat pinch of salt. Cook, stirring, until the onions are beginning to wilt, 2 minutes, then add in the bacon and thyme and continue to cook until the onions are soft, 2 minutes more. Set aside to cool.

In a small bowl, stir together the creme fraiche, chives and remaining egg yolk; season with ½ teaspoon salt and a few grinds of pepper. Remove the pastry from the freezer. Spread the crème fraiche over the pastry, avoiding the edge. Top with the grated cheese, then the bacononion mixture. Transfer to the oven and bake, rotating the pan once, until the pastry is golden brown and crispy (use a spatula to lift the tart and check the underside), 22 to 25 minutes. Transfer to a wire rack and let cool 10 minutes, then slide onto a cutting board and cut into 8 even squares.