Pulse mushrooms in a food processor until finely ground, about 10 pulses.

Heat oil in a Dutch oven over medium heat until shimmering.

Add processed mushrooms, onion, bell pepper, celery, and 0.25 tsp sea salt and cook until vegetables begin to soften, about 5 minutes.

Stir in garlic, Soy Sauce, and tomato paste and cook until fragrant, about 1 minute.

Stir in beef, breaking up meat with a wooden spoon, and cook until no longer pink, about 5 minutes.

Stir in tomato sauce, diced tomatoes with their juices, and broth, scraping up any browned bits.

Cover, reduce heat to low, and simmer until beef and vegetables are tender, about 20 minutes.

Plate beef and vegetable mixture atop spaghetti squash.

Season with sea salt and pepper to taste and serve. Here is the approximate nutritional information per serving, based on the ingredients listed (yields 6 servings): Per Serving