Combine shrimp and lime juice in a large bowl making sure all of the shrimp is covered by lime juice. Let sit in the refrigerator for 45-60 minutes or until shrimp is pink and opaque.
Once shrimp is “cooked,” remove from lime juice and mix with diced red onion, cucumber, tomatoes, jalapeno, cilantro and salt. Once combined, gently fold in avocado. You can add more lime juice here if you want.
To make “tostada”
Scoop ceviche on “tostada” and top with avocado slices, some hot sauce and more lime juice.
*you want to use fresh lime juice. Not the kind in a bottle. This makes a difference.