1. Add olive oil in a large skillet over high heat.
2. Add garlic and onion and sauté until onions are golden brown or about 4 minutes. Then, add the Marinara sauce, chicken stock, chili flakes, salt, and pepper and Spaghetti
3. Bring to a boil; reduce heat and simmer, stirring occasionally, until the liquid is almost totally absorbed by the pasta (about 8 minutes or so)
5. Stir in the shrimps and spinach until the shrimps becomes pink and the spinach begins to wilt or about 3 minutes.Top with Parmesan cheese before serving.