Creating the perfect Mexican Shrimp Cocktail can be easy if you follow these simple steps:

1. Cook the Shrimp: Bring a large pot of salted water to a boil. Add the shrimp and cook for 2-3 minutes until they turn pink and opaque. Drain and let them cool.
2. Prep the Ingredients: While the shrimp are cooling, prepare the onion, jalapeño, cilantro, cucumber, and avocado, ensuring they are finely diced. Set aside.
3. Make the Sauce: In a large mixing bowl, combine the tomato ketchup and lime juice. Mix well until combined.
4. Mix It Up: Add the cooled shrimp to the sauce mixture, followed by the chopped onion, jalapeño, cilantro, and cucumber. Stir gently to coat all the ingredients with the sauce.
5. Season: Taste the mixture and season with salt and pepper, adjusting according to your preference.
6. Add Avocado: Gently fold in the diced avocado, taking care not to mash it.
7. Chill: Cover the bowl and refrigerate the shrimp cocktail for at least 30 minutes to allow the flavors to meld.
8. Serve: Once chilled, stir the mixture once more before serving in individual bowls or cups, garnished with lime wedges.

These steps outline a simple process for making a restaurant-quality Mexican Shrimp Cocktail in the comfort of your own home.