Bring a (oven-safe) stock pot of water to a boil. Add the pasta and cook until al dente. Drain and place the empty stock pot back on the stove.
Add the oil to the pot over medium heat. Add the onion, garlic, zucchini, squash and dry seasonings. Cook for 5 minutes, stirring frequently. Add the spinach and toss until wilted. Pour in the marinara and simmer for 10 minutes, stirring frequently. Taste and adjust the seasonings as needed.
Pour in the pasta and toss to combine. Remove from the heat. Add dollops of the Boursin to the top of the pasta. Sprinkle on the vegan mozzarella. Place in the oven under the broiler until the cheese is melted.
Remove from the oven, top with fresh oregano and spoon onto plates.
