Preheat the oven to 425°F (220°C) and line a baking sheet with parchment paper.
Cut the puff pastry into 9 equal rectangles. Lightly score a smaller rectangle inside each piece, leaving about a ¼-inch border without cutting all the way through.
Mix the ricotta, Parmesan, basil, garlic powder, oregano, salt, and pepper until smooth. Keep the beaten egg nearby for the egg wash.
Spread about 1½ tablespoons of the ricotta mixture inside each pastry border.
Arrange the tomato slices over the cheese and lightly brush the tomatoes with olive oil.
Brush the pastry edges with beaten egg. Bake for 18–20 minutes, until the pastry is puffed and golden.
Cool for 5 minutes, then garnish with fresh basil, flaky salt, and black pepper before serving.