In a skillet, heat olive oil or water over medium heat. Add mushrooms, onion, and garlic; sauté for about 5 minutes, until the onions are translucent. Toss in your Italian seasonings for the last minute. Let cool for a few minutes.

In a food processor, pulse walnuts or sunflower seeds until coarsely ground. If using old-fashioned oats, process them together with the nuts. Add the sautéed veggies and beans to the processor and pulse until just combined, keeping some texture. Season with sea salt and pepper to taste.

Roll the mixture into 1.5 to 2-inch balls and place them on a lined baking sheet.

For baking, preheat oven to 400°F. Bake meatballs on the lined baking sheet for about 25-30 minutes or until golden brown and firm.

For stovetop, heat a little oil in a skillet and cook the meatballs for about 15-20 minutes, turning occasionally until they're brown and crispy.

Combine freshly baked meatballs with marinara sauce in a pan over low heat for about 10 minutes to let flavors meld.

Meanwhile, cook pasta according to package instructions. If using spaghetti squash, roast it cut-side down at 400°F for 30-40 minutes, scoop out the strands afterward.

Plate spaghetti, generously topping it with the sauce and meatballs. Garnish with fresh parsley or basil and a sprinkle of almond Parmesan, if desired.

Place leftovers in an airtight container for up to 5 days in the fridge.