- 3 oz Sartori SarVecchio® Parmesan cheese, divided
- 2 Tbs butter, cubed
- 1 large sweet onion, halved and thinly sliced
- 1/4 tsp each salt and pepper
- 1/3 c heavy whipping cream
- 1 sheet frozen puff pastry, thawed
- 1/2 lb fresh asparagus spears, trimmed and blanched
- 8 cherry tomatoes, halved
- 2 tsp lemon zest
Heat oven to 425°F.
Shred 1/4 c parmesan. Finely shred remaining parmesan.
Melt butter in a heavy, large skillet over medium heat. Add onion, salt and pepper; cook for 10 minutes, stirring frequently.
Reduce heat to medium-low. Cook for 20-25 minutes longer or until onion is golden brown, stirring occasionally.
Gradually stir in cream. Bring just to a boil; cook and stir until cream is reduced and thickened. Remove from the heat.
Stir in shredded parmesan until melted; set aside.
Heat oven to 425°F. Line a 15 x 10-inch baking pan with parchment paper.
Unfold pastry on a lightly floured surface; roll out pastry to a 15 x 10-inch rectangle.
Place pastry in prepared pan. Score a 1/2-inch border on edges of pastry with sharp knife. Prick pastry with a fork.
Spoon reserved onion mixture to edges of scored pastry. Arrange asparagus and tomatoes on top.
Bake for 18-20 minutes or until pastry is golden brown.
Sprinkle with finely shredded parmesan. Cool on a wire rack for 10 minutes.
Sprinkle with lemon zest just before cutting. Serve warm or at room temperature.