1. Preheat the oven to 350℉
2. Line your baking sheet (around 10x13 inches) with parchment paper In a large bowl, add the eggs, Parmesan cheese, salt, and pepper to taste. Whisk well.
3. Pour on the prepared baking sheet and bake for about 12 to 15 minutes until the frittata is set and lightly golden on top.
4. In the meantime, heat the oil in a large frying pan over medium-high heat, and saute' the spinach turning them often until wilted. Salt and pepper to taste.
5. When ready, flip the frittata onto another piece of parchment paper. Remove the baking paper on top and let cool for a few minutes.
6. Spread with ricotta cheese and distribute the spinach on top.
7. Helping yourself with the parchment paper, roll up the frittata on the longer side.
8. Roll tightly, wrap in the paper and refrigerate for 15 minutes or until ready to serve.
9. Cut in one-inch slices. You should get about 12 rolls. If you like top with cherry tomatoes and secure with a toothpick. Enjoy!

Recipe Notes: These frittata rolls are very versatile and can be stuffed with your favorite (ham and cheese, cream cheese and smoked salmon, prosciutto and mozzarella)