Bring a pot of water to a boil, add the peeled and deveined shrimp, and poach for 2-3 minutes until pink and opaque.
Drain the shrimp and immediately plunge them into an ice bath to stop the cooking process.
Once cooled, pat the shrimp dry and chop into bite-sized pieces if they are large.
In a large glass bowl, whisk together the lime juice, extra virgin olive oil, sea salt, and black pepper.
Add the diced cucumber, finely diced red onion, diced Roma tomato, minced jalapeño, and chopped cilantro to the bowl.
Gently fold in the poached shrimp and the diced avocado until well combined.
Cover and refrigerate for at least 15 minutes to allow the flavors to meld before serving.