Add the olive oil, vinegar, lemon, garlic, seasonings, and parsley to a bowl.
Using a whisk, stir well to combine the ingredients.
Add the seasonings and mix again. Set the dressing aside.
To prep the shrimp, remove the tails, roughly chop them.
Add the shrimp to the dressing.
Stir well with a spatula to coat the shrimp with the dressing.
Taste and adjust the salt.
Serve immediately or allow it to chill for an hour.
Notes
I like to mix the dressing before chopping the shrimp. It allows the flavors to come together and the acid to mellow out the garlic.
When chopping the shrimp, I don't try to do it perfectly. I like the different shapes and sizes because they absorb the dressing better.
Also, think about how you're gonna serve it. If you're serving this with crackers, it will be easier To eat if you chop them small. You can leave the pieces a little bigger if serving this as a salad or side dish. A more dramatic presentation is to leave the shrimp whole, but I like the dressing to soak into all the nooks and crannies of the chopped shrimp.