Put the olive oil in a large skillet.
Sautee the onion until it’s soft.
Add the garlic, salt, pepper, and oregano.
When the mix becomes heady, pour in both the Marinara and Alfredo sauces.
Simmer for 10 minutes.
Slowly add the cheeses, stirring as you go.
When they are totally melted and integrated, your sauce is ready for your favorite pasta. This is enough for about 1 lb. of spaghetti.