Prepare pasta according to package directions for al dente consistency. Drain and set aside.
While the pasta is cooking, heat the olive oil in a large deep skillet over medium heat. When the oil is hot, add the sliced vegan sausage. Cook, moving the sausage around the pan frequently, until heated through and browned on both sides. Remove cooked sausage to a paper towel-lined plate.
Into the skillet, add bell peppers and onion. Continue cooking 3 minutes, stirring frequently until peppers and onion are softened. Add garlic and continue cooking an additional 1 minute. Add the sausage back into the skillet with the vegetables.
Add the diced tomatoes, dried basil, dried oregano, sea salt, crushed red pepper flakes. Stir to combine all ingredients. Cook 5 minutes over medium heat.
Into the skillet, add the cooked pasta. Stir to combine.
Reduce heat to medium-low, cover the pan, and allow to simmer for about 5 minutes.
Adjust seasoning to taste. Serve hot.