1 cup all-purpose flour
2 large eggs
2 tablespoons roughly chopped fresh spinach
3½ tablespoons ricotta
3½ tablespoons mascarpone
3½ tablespoons grated Parmigiano-Reggiano
¼ teaspoon freshly ground black pepper
1. Make the dough: To a large bowl, add 2/3 cup of the flour. Crack each egg in the bowl, one at a time, mixing with a wooden spoon until a dough consistency forms. Transfer the dough to a lightly floured surface and knead with both hands, adding the remaining 1/3 cup of flour as necessary if the dough is too sticky. Wrap the dough with plastic wrap and refrigerate for 2 hours.
2. Make the filling: In a medium bowl, combine the spinach, ricotta, mascarpone, Parmigiano-Reggiano and black pepper. Refrigerate until the dough is ready.
3. Unwrap the dough and transfer it to a lightly floured work surface. Dust a rolling pin with flour and use it to roll the dough into a 16-by-10-inch circle, turning it over four times while rolling.
4. One at a time, add a generous teaspoon of filling to the dough in rows, leaving a ½-inch between each spoonful. Use a pastry wheel or pasta cutter to cut between each mound. Fold the dough in half to form a triangle over the filling. Using your index finger and thumb, fold the edges of the dough toward each other and pinch them together.
5. Bring a large pot of salted water to a boil over high heat. Add the tortelloni and cook for 3 minutes, stirring occasionally. Drain the tortelloni in a colander. Transfer to a plate and sprinkle with Parmigiano-Reggiano. Serve immediately.