Add 2 Tbsp olive oil to a large skillet. Turn the heat to medium high. Allow the pan to heat up for 30 seconds, then add the onion, garlic, and ½ tsp salt. Cook over medium-high heat for 6 minutes, until the pan starts to get dry and the onion begins to brown.
Now add ¼ cup water to the pan. Cook for 2 minutes. The water will reduce by half.
Now turn the heat down to low, and cook the onion for an additional 2 minutes.
Add the fresh tomato
Next, add the fresh tomatoes, ½ tsp salt, and the last Tbsp olive oil. Turn the heat up to medium, and cook for 7 minutes, until the tomatoes have broken down a bit and released their juices.
Add the canned tomatoes
Now add the canned tomatoes and their juices, the last ½ tsp salt, the brown sugar, Italian seasoning, and the parsley.
Over medium low, bring the mixture to a simmer. This will take about 6 minutes.
Once simmering, allow the tomato mixture to simmer for 12-15 minutes, stirring occasionally.
Cook the pasta
While your tomato sauce is simmering, cook the pasta according to package instructions, but subtract 2-3 minutes from the cook time. We want the pasta to be slightly undercooked. It will finish cooking in the oven.
Now is also a good time to toss together the mozzarella and cheddar. We want the cheddar to be evenly distributed throughout the mozzarella.
Combine the pasta and sauce
Once the pasta finishes cooking, drain it, and put in back in the pot you cooked it in.
Now add the tomato sauce to the pot with the pasta, and mix it all together until the sauce evenly coasts all the pasta.
Get ready to bake
Preheat the oven to 375 degrees.
Oil a 9x13 inch-baking dish. Spread half of the pasta/tomato sauce mixture evenly in the bottom of the pan.
Now sprinkle half of the mozzarella/cheddar mixture on top, followed by half of the Parmesan.
Spread the rest of the pasta/tomato sauce mixture over the cheese. Last, sprinkle the remaining mozzarella/cheddar mixture on top, followed by the remaining Parmesan.
Bake the pasta
Bake the pasta, uncovered, for 15-20 minutes at 375 degrees, until the cheese is bubbly and slightly browned.
Serve and enjoy!
Notes
This baked pasta is vegetarian.This baked pasta is gluten-free if you use gluten-free pasta.