Unsalted butter for greasing tart pan
1 sheet (1/2 of 1.1 lb pkg) frozen puff pastry, thawed
Flour for dusting work surface
2 Tbsp olive oil, divided
1 medium shallot, peeled, trimmed, and finely chopped
1 tsp Green Giant™ Fresh thyme leaves
1/8 tsp crushed red pepper flakes
1 lb Green Giant™ Fresh Baby Bella Mushrooms, washed, stems trimmed, sliced crosswise into 1/4" pieces
1 lb kale, washed, woody stems and large ribs removed, leaves coarsely chopped
1 cup ricotta cheese
3/4 cup Pecorino Romano or Parmigiano-Reggiano cheese, grated, divided
2 large eggs, lightly beaten
Kosher salt
Freshly ground black pepper