1 pkg (397 g) frozen puff pastry, thawed
1 egg yolk
2 tbsp (25 mL) granulated sugar
1/2 cup (125 mL) mascarpone or cream cheese
1 tbsp (15 mL) milk
2 tbsp (25 mL) icing sugar
1/4 tsp (1 mL) cinnamon
1/4 tsp (1 mL) vanilla
6 cups (1.5 L) hulled strawberries (about 1-1/2 lb/750 g)
1/4 cup (50 mL) strawberry jam, strained, or jelly, melted
Line pizza pan with parchment paper; set aside.
Cut puff pastry in half to separate blocks; stack 1 on top of the other. On lightly floured surface, roll out pastry to 12-inch (30 cm) square. Trim corners to make circle. Transfer to prepared pan. With fork, prick pastry all over.
In small bowl, whisk egg yolk with 1 tsp (5 mL) water; brush over pastry. Sprinkle with granulated sugar. Bake in bottom third of 400°F (200°C) oven until puffed and golden, 15 to 18 minutes. Let cool on rack. (Make-ahead: Cover loosely with plastic wrap; store for up to 24 hours.)
Meanwhile, in bowl, whisk mascarpone cheese with milk until smooth; whisk in icing sugar, cinnamon and vanilla. Set aside. Slice strawberries in half; set aside.
Spread cheese mixture over pastry, leaving 1/4-inch (5 mm) border. Arrange strawberries in concentric circles on top; brush berries with jam. Serve immediately.