Bring a large pot of salted water to a boil. Add the linguine and cook for 2-3 minutes less than the package recommends. For example my pasta recommends a cooking time of 11 minutes. I cook it for 9 minutes. This will keep the pasta from getting mushy while in the oven.

Drain and rinse pasta. Set aside.

Mix 1 Tablespoon flaxseed meal with 2.5 Tablespoons water Set aside.

Preheat the oven to 400 degrees. Cut cauliflower in small pieces, peel garlic cloves. Line a baking sheet with parchment paper. In a large bowl toss cauliflower and garlic with vegetable broth, salt, and pepper. Place cauliflower and garlic on parchment paper. Bake for 20 – 25 minutes until cauliflower is soft. Remove from the oven and let cool.

Reduce oven temperature to 375 degrees.

Put cooled cauliflower garlic mixture in a blender. Add oat milk and puree until it is smooth and creamy. Set aside.

Sauté onions until soft 2-3 minutes, adding a splash of water to prevent sticking.

Add the mushrooms and sauté for another 4 minutes.

In a large bowl, mix pasta and flaxseed meal until well combined.

Transfer the pasta to the pie dish lined with parchment paper. Arrange the noodles on the bottom and up the side of the dish to form a crust.

Spread onion mushroom mixture over the pasta.

Spread the cauliflower garlic puree over the onions and mushrooms.

Add 1/2 of the marinara sauce as the final layer.

Sprinkle pie with faux parmesan cheese or nutritional yeast.

Bake uncovered for 35 – 40 minutes or until pasta is a golden brown.

Let the pie cool for 10 – 15 minutes before cutting.

Spoon extra sauce on top if desired.