Bring a small pot of water to a boil and poach the shrimp for 2-3 minutes until they are opaque and pink.
Drain the shrimp and immediately transfer them to an ice bath to stop the cooking process and keep them tender.
Once cooled, pat the shrimp dry and chop them into bite-sized pieces, then place them in a large glass mixing bowl.
Add the diced cucumber, finely diced red onion, diced roma tomato, and chopped cilantro to the bowl.
In a small jar or bowl, whisk together the lime juice, olive oil, chili powder, sea salt, and black pepper.
Pour the chili-lime dressing over the shrimp and vegetables, tossing gently to ensure everything is well coated.
Carefully fold in the diced avocado just before serving to maintain its creamy texture and vibrant green color.