Preheat oven to 450 degrees and line baking dish with aluminum foil or parchment paper. Cut spaghetti squash in half using chef's knife and scrape out the seeds with a fork. Place squash face down and bake for 30-40 minutes until fully cooked. Scrape out the spaghetti squash with a fork and place in a bowl.
Preheat oven to 375 degrees. Toss mushrooms with oil, salt, and pepper on baking sheet. Bake for 30 minutes turning frequently with a spatula until crisp.
Heat olive oil on skillet over medium heat and cook onion and garlic until soft and browned. Remove from heat.
In blender, combine the onion, garlic, tofu, water, lemon juice and salt. Blend on high until creamy consistency. Should be around 2 minutes. Let the sauce sit for about 5 minutes to allow to thicken.
Add the sauce to the spaghetti squash and top with the shiitaki bacon and parsley garnish.
Serve and enjoy!