Preheat the oven to 400 degrees. Grease a 9 x 13 inch baking dish and set aside.

Drain the tofu by wrapping it up in thin kitchen towels (or paper towels) and pressing down firmly. Repeat until the tofu is drained as much as possible. Place the tofu in a large mixing bowl and mash with a fork until crumbled. Add the nutritional yeast, Italian seasoning, garlic, and season with salt and pepper. Set aside.

Slice the bulbous end off of the butternut squash and reserve for future use. Take the neck and peel it, first slicing off the top. Slice the squash lengthwise halfway through, careful not to pierce through the center. Spiralize the squash on Blade A. Set aside the squash slices.

Heat the oil in a medium pot over medium-high heat. Once oil is shimmering, add the onions, garlic and bell peppers and cook until crisp-tender, about 5 minutes. Add the marinara sauce and cook another 5 minutes to heat the sauce.

Spoon the sauce into the baking dish to cover the bottom. Lay out the butternut squash noodles in an even layer. Spread one-third of the tofu mixture over the squash and then add more sauce. Repeat, ending with sauce. Cover the dish with foil and bake until the squash is tender, about 45 minutes. Uncover and let rest at least 10 minutes before serving.