Prep time: 15 minutes |  Cook time: 20 minutes

Cook pancetta in large skillet set over medium heat, turning once, for 5 to 7 minutes or until crispy. Transfer to paper towel–lined plate; crumble and set aside.

On lightly floured surface, unroll pastry into 10-inch square; cut into six 5 x 3 1/4-inch rectangles and place on parchment paper–lined baking sheet. Prick all over with a fork.

Spoon mascarpone evenly over pastry rectangles, leaving 1/2–inch border all around; top each one with 4 peach slices. Whisk apricot jam with 1 tbsp water; brush over peach slices and edges of tarts. Sprinkle with thyme and crumbled pancetta.

Bake in 400°F oven for about 20 minutes or until edges of pastry are puffed and golden brown. Let cool for 5 to 10 minutes before serving. Serve warm.