Blend 8 oz tomatoes in your food processor until a chunky liquid is formed.
Heat a non-stick skillet over medium heat. Stir 2 tbsp olive oil and 2 tbsp garlic until fragrant.
Add 12 oz peeled shrimp along with 1/2 tbsp Italian seasoning, 1/2 tsp paprika, 1/2 tsp pepper. Stir for about 30 seconds, then add 1/2 tbsp butter and cook for 3 minutes. Put the shrimp away.
Add 2 oz onions and 1/2 tbsp butter to the same skillet, and stir for about 1 minute or until translucent. Stir in 2 tbsp tomato paste and cook until it melts and coats the onions.
Add the blended tomatoes in and stir for 2 minutes. Just as it feels dry and almost sticks to the skillet, add 1/2 tsp oregano, 1/2 tsp salt, and 1/2 cup unsalted chicken broth. Scrape the bottom to release flavorful bits and simmer for 3 minutes.
Add the shrimp and simmer over low heat for another 5 minutes.
Turn off the heat and sprinkle in 2 tbsp basil, 0.5 parmesan, and 1/2 tsp red pepper flakes. Serve with 18 oz cooked spaghetti.