Preheat the oven to 400F. Wash and destem the portobello mushrooms. Place on a baking sheet and brush 2 tablespoons of olive oil on the tops and bottoms. Sprinkle with basil, oregano, and salt. Bake for 10 minutes until mushrooms are tender.
While the portobello is baking, make the tempeh sausage. Heat 1 tablespoon of olive oil in a large sauté pan over medium heat. Add tempeh crumbles, soy sauce, Worcestershire sauce, and spices. Sauté for about 5 minutes, until tempeh is slightly browned. Add water and cook until all the water has absorbed and the tempeh is cooked all the way through.
Remove from heat and set aside. Return the pan to medium heat and add onions, peppers, and garlic. Sauté for 5-7 minutes until the onions are translucent and fragrant.
To assemble the pizzas, fill each portobello with ¼ cup pizza sauce. Top with tempeh sausage, mounding the top. Cover with the onion/pepper mixture and cherry tomatoes. Return the pizzas to the oven for an additional 10 minutes.
Serve with vegan parmesan cheese and red pepper flakes.