1. Preheat your oven to 400°F (200°C) and line a baking sheet with parchment paper.
2. In a skillet, heat olive oil over medium heat. Add garlic and spinach, sautéing until the spinach is wilted and the garlic is fragrant, about 2-3 minutes. Remove from heat and let cool slightly.
3. In a mixing bowl, combine ricotta, feta, the cooled spinach mixture, salt, pepper, and nutmeg. Stir until well combined.
4. Roll out the puff pastry on a lightly floured surface. Cut each sheet into squares, approximately 4×4 inches.
5. Spoon about 1-2 tablespoons of the cheese and spinach mixture onto each square. Fold the pastry over to form a triangle, pressing the edges with a fork to seal.
6. Brush the tops with beaten egg and sprinkle with sesame seeds if desired.
7. Place the pastries on the prepared baking sheet and bake for 20-25 minutes, or until the pastry is golden brown and puffed.

Remember, the joy in cooking lies in making the recipe your own. Don’t hesitate to play around with the fillings or spices. Just like my abuela taught me, sometimes the best dishes come from trusting your instincts.