Make the gnocchi.  

In a fine-mesh strainer set over a bowl, spoon the ricotta into the strainer.  Cover with plastic wrap and place in the refrigerator.  Allow the ricotta to drain for at least 30 minutes, or even better for2-3 hours.  Occasionally press the ricotta with the back of a large spoon to remove as much liquid as possible from the cheese.

Transfer the ricotta to a large mixing bowl.

Add the egg yolks and stir till just combined.

Stir in the flour, Parmesan cheese, salt, and pepper.  Stir until well combined, but do not overmix.

The dough will feel too wet and sticky.  If it feels too wet to work with, add another tablespoon of flour and mix well.

Turn the dough out onto a flour-dusted cutting board.

Form the dough into a ball.

With a sharp knife, cut the ball into 8 wedges.

Using your hands, roll each wedge into an even log about ¾-inch wide.

Cut into bite-sized (about 1-inch) pieces.

Roll gently into the flour and place onto a baking sheet.  Set aside.

Repeat with the remaining wedges.

Boil a large Dutch oven of heavily salted water.  Carefully transfer the gnocchi, a few pieces at a time.  Stir well.  You may have to work in batches.

Cook until the gnocchi begins to float – about 45 seconds – use a wire spider to remove the gnocchi to a baking pan.  Set aside.

Meanwhile while cooking the gnocchi, make the sauce.

In a large bowl, pour in the canned tomatoes.

Use an immersion blender to blend until smooth.  Set aside.

In a large pot, heat the olive oil over low heat until shimmering, about 2 minutes.

Add in the onions and garlic and cook until translucent, about 10 minutes.

Pour in the tomatoes.  Cook, stirring often for about 30 minutes.

Stir in the oregano, basil, salt, pepper, and butter.  Cook, stirring for another 10 minutes.

In a large skillet, pour most of the sauce into the skillet over medium-low heat.

Add the gnocchi to the skillet and toss in the sauce to coat fully. 

Allow to simmer and the flavors to meld together for about 5 minutes.

Remove from heat.

Spoon the gnocchi and sauce into serving bowls.  Top with shaved Parmesan cheese and serve hot.