1. Add the olive oil and onion to a small pan over medium heat. Sprinkle with a pinch of salt and black pepper and saute until soft.
2. Add the spinach and cover the pan. Continue to saute until the spinach is warmed through and losing moisture.
3. Remove the lid and add the garlic. Mix well and saute another few minutes. Move the mixture to a mixing bowl and allow it to cool.
4. Add the parmasan, ricotta, and egg to the bowl. Fold all components togther until well mixed.

Roll out sheets of pasta dough. Place a heaping teaspoon of filling every few inches at the center of the pasta sheet. Lightly wet the edges and the region between each bit of filling, then fold the sheet onto itself to enclose the filling — be sure to push out as much air as possible before the dough seals. Cut between each bit of filling and press all seams to seal completely. Dust with flour and transfer each to a sheet pan.

The ravioli can be frozen or cooked immediately.

Tortellini

This filling works well for tortellini, too. Roll the pasta dough into a large circle and cut 2 inch rounds. Place ¼ teaspon of filling on the center of each circle. Wet the perimeter of the dough and fold in half, pinching the edges shut and squeezing out any air. Bring the two points of the crescent together and pinch. Dust with flour, freeze or cook immeidately.