Time 1½ hours

Serving 8 to 10

• 1 (16-ounce) package phyllo sheets, thawed (about 18 sheets)
• ¾ cup melted butter
• 1 cup/320 grams best-quality apricot jam, or use orange marmalade
• ½ cup/50 grams chopped pistachios or walnuts
• 8 large apricots (1½ pounds/680 grams), halved, pitted and cut into 6 wedges each (about 3 cups)
• ⅓ cup/67 grams granulated sugar

Step 1
Heat oven to 375 degrees. Lay 1 sheet phyllo on a parchment-lined 12-by-18-inch rimmed baking sheet. Drizzle with 1 tablespoon butter and brush to coat the entire phyllo sheet.

Step 2
Top with another sheet and butter as above. Repeat with 7 more sheets, for a total of 9, buttering as you go. The final, top layer should also be buttered. (The rest of the phyllo can be wrapped and frozen for future use.)

Step 3
Dot the top sheet with jam by the teaspoon, then, using a spatula, spread the jam to cover the entire sheet, leaving a 2-inch border.

Step 4
Sprinkle a layer of half the chopped pistachios over the jam. Place the apricot wedges, skin-side down, in even rows across the surface, then sprinkle again with remaining pistachios.

Step 5
Carefully fold over the edges on all sides of the tart to make a 10-by-16-inch rectangle. Brush folded sides with butter. Sprinkle sugar generously over apricots and folded edges.

Step 6
Bake until pastry is golden and apricots begin to color, about 1 hour. Cool for 15 minutes, then cut into squares. Serve warm or at room temperature.