I always use Kosher salt in my kitchen! If using table salt, start with half the amount and adjust to taste, as it is much "saltier" by volume.
Instructions
Heat the olive oil in a large skillet over medium-high heat. Add the sausage and cook, breaking it up into crumbles. When the sausage is about halfway cooked, stir in the onions and continue cooking until the sausage is browned and cooked through.
Now add in the garlic and cook until fragrant, about 30 seconds.
Stir in the tomato sauce, diced tomatoes, salt, pepper, red pepper flakes, dried basil and dried oregano. reduce the heat and simmer for 20 minutes, stirring often.
Remove from the heat and stir in the al dente pasta. Transfer to a 9x13 baking dish and top with the mozzarella and parmesan. Cover with foil and bake in a 350°F oven for 30 minutes.
Remove the foil and broil for a few minutes until golden and bubbly. Garnish with fresh basil if desired. Enjoy!
Notes
Storage Tips:Once cooled, store in an airtight container for up to 4 days.Make ahead - Assemble the casserole following the directions, then cover with plastic wrap and refrigerate up to one day before baking.Remove from the fridge to come up to room temp before replacing the plastic wrap with foil and baking. More time may need to be added to the bake time.