Toss the diced eggplant with some olive oil (enough to coat the eggplant).
Line a baking sheet with parchment paper and place the eggplant in a single layer on the parchment paper. Bake for about 25 minutes until cooked and fully roasted (slightly browned, but not burned).
To Make the Caramelized Onions:
Heat 2-3 tbsp olive oil on a non-stick large pan on low-medium heat. Add the thinly sliced white onions and an pinch of salt, and saute until they become completely translucent, slightly brown, and just caramelized (~25 minutes). Be sure to mix frequently. If you find that the onions start sticking to the bottom of the pan or start to burn, feel free to add a little more olive oil.
Once the onions are caramelized, de-glaze the pan by adding a slash of cooking wine to the pan.
To Make the Sauce:
Heat 3 tbsp of oil in a medium sized pot on medium heat.
Add 8 cloves minced garlic and some dried red crushed peppers (more or less to taste depending on spice preference). Fry for ~30 sec. until fragrant. Be careful not to burn them.
Add the can of diced tomatoes. Once the sauce is simmering, reduce the heat to low-medium and simmer uncovered for about 15-20 minutes or until the sauce thickens and reduces to about 2 cups.
Add the chopped basil. Season to taste with salt, pepper, and white sugar (if needed). Cook for another 5 minutes. Turn off the heat and set aside (note: if you are almost done with the recipe, feel free to keep heating the sauce at lowest setting possible to keep the sauce hot until the pasta is ready).
To Assemble the Pasta:
Set a large pot of water to boil. Add a generous pinch of salt and a drizzle of olive oil. Once the water is boiling, add the penne pasta and cook al dente.
Add the roasted eggplant to the de-glazed pan with caramelized onions.
Add the hot tomato sauce and cooked penne pasta. Toss everything to combine.
Season with salt and pepper to taste. Garnish with some freshly chopped basil.
Top with some fresh Parmesan cheese (omit for vegan option), and serve hot!
Gluten-Free Pasta - There are many gluten-free pasta options you can choose from. My favorite for this dish is brown rice pasta.