Sauté the veggies. Heat 1 tablespoon oil in a large nonstick sauté pan over medium-high heat. Add the onion and carrot and sauté, stirring occasionally, for 4 minutes. Add the bell pepper, zucchini and the remaining oil. Sauté for 5-8 more minutes, stirring occasionally, until the vegetables are tender and lightly caramelized around the edges. Add the garlic and tomato paste and sauté for 2 more minutes, stirring frequently. 

Blend. Transfer the entire veggie mixture to a blender. Add beans, oregano, salt, pepper and ½ cup water and purée until completely smooth. (If need be, add in extra water so that the sauce can blend.) Add the Parmesan and purée until smooth.

Serve or store. When combining the marinara with pasta, I recommend reserving and adding in some of the starchy pasta water (at least ¼ cup per 1 cup of the marinara) to thin out the marinara and help it cling to the pasta. Any leftover marinara can be refrigerated in a sealed container for up to 3 days or frozen for up to 3 months. Enjoy!