In a bowl, combine all the brine ingredients and whisk until mixed well. Let sit at room temperature while you prepare the shrimp. In a pot, bring water with a heavy pinch of salt to a boil. Add in shrimp and turn off the heat, letting the shrimp cook until fully pink and cooked through, about 3–5 minutes. Remove shrimp and set aside, discarding cooking liquid. To clean jars or food safe containers, add the cooked shrimp in layers and then pour the liquid mixture over the shrimp, being sure that the shrimp are completely submerged. If they are not, add more oil. Refrigerate for at least 3 hours but ideally overnight. Serve shrimp cold or at room temperature. Toss if not eaten after 3 days, as your shrimp will get gross and mushy from sitting in too much acid for too long.