Mushroom Tetrazzini

1 lb spaghetti
2 lbs button mushrooms, sliced
1 leek, washed well, chopped
1 red pepper, diced small
1 tablespoon butter or vegan butter
½ cup flour or potato starch
1 stick butter or vegan butter
1 tablespoon sea salt or to taste
½ teaspoon black pepper
5 cups vegetable stock
1 ½ cups coconut milk
½ cup parmesan cheese or vegan parmesan cheese
4 oz mozzarella cheese or vegan mozzaralla cheese
½ cup bread crumbs or gluten free bread crumbs

1. Cook spaghetti until just barely al dente. Rinse in cold water and set aside.
2. Melt butter in a heavy  saucepan over medium heat. Add flour and stir. Cook for 1 minute. Whisk in stock, coconut milk, salt, pepper, and parmesan cheese. Cook for 2-3 minutes, whisking constantly. Remove from heat.
3. Heat 1 tablespoon butter over medium heat in a large skillet and add mushrooms, leeks, and red pepper. Saute about 10 minutes until mushrooms are cooked and pepper is soft. Drain.
4. Combine pasta, sauce, and vegetables in a large bowl or in spaghetti pot.
5. Spread mixture into a greased, large, deep baking dish. Mix bread crumbs and mozzarella in small bowl and sprinkle over pasta. Cover with foil and bake at 350°F for 45 minutes. Remove foil and bake for 15 more minutes.