In a small bowl, combine the chopped red onion, lime juice, olive oil, kosher salt, and black pepper.
Let the mixture sit for at least 5 minutes to soften and mellow the onion flavor.
In a large mixing bowl, add the chopped shrimp, diced avocado, diced tomato, and jalapeño.
Pour the lime dressing over the shrimp mixture.
Add the chopped cilantro.
Gently toss everything together until evenly coated.
Taste and adjust the seasoning with additional salt and pepper if needed.
Serve the Shrimp and Avocado Salad Recipe immediately for the freshest flavor.