Heat olive oil in large pan. Add Pancetta and saute until it is slightly brown. Add the onions and garlic and continue to cook stirring occasionally until the onion begins to turn translucent and the garlic is fragrent.
Add Spinach to pan and toss and cook until the spinach is just wilted. Remove from heat and allow to cool completely.
Mix Egg, Ricotta, and Parmigiano in a medium bowl. Add the cooled Spinach mixture and stir to combine. Set aside
Use this filling to stuff your favorite" stuffable" pasta. Canneloni, Manicotti, Ravioli or Lasagna all would love to have this filling between their sheets.