Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
Unfold the puff pastry on a lightly floured surface and cut it into 8 equal rectangles. Place them on the prepared baking sheet.
Score a border around each piece of pastry, about ½ inch from the edge. Don’t cut all the way through—just enough to help the edges puff up.
Brush the borders with the beaten egg.
In a bowl, mix the ricotta, mozzarella, and parmesan together. Spoon a bit of the mixture into the center of each rectangle.
Top with halved cherry tomatoes, cut side up. Drizzle lightly with olive oil and sprinkle with salt, pepper, and oregano.
Bake for 20–22 minutes, or until the pastry is golden and the cheese is melted and bubbling.
Remove from the oven and let them cool for a few minutes. Garnish with fresh basil if using, then serve warm or at room temp.