Place all ingredients in a blender, pulse 4-5x. I do not completely puree the sauce, I keep it the consistency of a medium salsa as seen in the picture. Start by adding 1/4 cup sriracha sauce, taste test and add more if you like it spicier.
I make the cocktail sauce either the night before or the morning of that I'm going to serve it. This gives some time for all of the flavors to blend together even more. This sauce is a lot like chili soup, the flavors are even better if it's given time to marinate.
To make the shrimp place 6 cups of water in a medium to large saucepan along with a few springs of parsley, one garlic clove minced, a lemon cut into wedges, and 1 tsp salt, simmer for 10 minutes.
After 10 minutes, add the shrimp simmer for 5 minutes or until shrimp turn pink, than run under cold water until the shrimp are completely cold. Refrigerate until ready to serve.