Mix 2 cups of flour with 4 eggs and 1 tablespoon of olive oil.
Knead until a smooth dough forms, then wrap in plastic wrap.
Place the dough in the refrigerator for at least an hour to rest.
While the dough rests, combine 1 cup of ricotta cheese, 1/4 cup of Parmesan, and 2 tablespoons of chopped spinach.
Season with salt and pepper.
Set the filling aside until needed.
Roll out the dough on a floured surface to about 1/16 inch thickness.
Cut into large squares for ravioli.
Use a pasta cutter for clean edges.
Place a small spoonful of filling in the center of each square.
Create a well and gently lay an egg yolk in the center of each well.
Brush the edges with water to help seal the pasta.
Cover the ravioli with another square, pressing out any air and sealing the edges.
Cook in simmering salted water for about 2 minutes.
The pasta should be al dente, with a runny yolk inside.