1-Prepare shrimp stock: Prepare shrimp stock by combining shrimp peels, 2 cups water, parsley, peppercorns, 6 cloves garlic, and salt in a pot. Bring to a boil, then simmer for 10 minutes. Strain and set aside 1 cup of the stock.

2-Cook pasta: Cook pasta in salted boiling water but drain 1 to 2 minutes before the package instructions are complete.

3-Sauté garlic and red pepper flakes: In a sauté pan over medium-high heat, heat 2 tablespoons olive oil. Thinly slice the remaining 4 garlic cloves and sauté them with ½ to 1 teaspoon red pepper flakes for about 1 minute.

4-Make the sauce: Add ¾ cup of the shrimp stock and bring to a simmer. Stir in grape or cherry tomatoes and canned diced tomatoes. Season with salt and black pepper, cover, reduce heat to low, and cook for 10 minutes.

5-Thicken the sauce: Remove the lid, increase heat to medium, and cook the sauce until it thickens, about 5 minutes.

6-Cook shrimp in sauce: Add shrimp to the sauce and cook for 2 minutes. Stir in 2 tablespoons cold butter and continue cooking until the shrimp is almost done, about 30 to 60 seconds.

7-Adjust seasoning: Adjust seasoning with salt, pepper, and additional red pepper flakes if desired.

8-Toss pasta with sauce: Toss the pasta into the sauce. If the sauce is too thick, thin it with some of the reserved shrimp stock.

9-Garnish and serve: Garnish with chopped parsley and Parmesan cheese before serving.