01 -
Bring a large pot of salted water to a boil. Remove from heat and add shrimp. Poach until shrimp turn pink and are cooked through, approximately 3 minutes. Drain and let cool.
02 -
Remove tails from poached or raw shrimp and cut into bite-sized pieces.
03 -
In a large bowl, combine shrimp, finely chopped red onion, jalapeños, lime juice, and orange juice. Season generously with kosher salt.
04 -
If poached, cover and refrigerate the mixture until cold, about 20 minutes. If curing raw shrimp in citrus, cover and refrigerate until shrimp becomes opaque and firm, between 15 to 30 minutes.
05 -
Stir in chopped cucumber, cherry tomatoes, and fresh cilantro. Season with salt and freshly ground black pepper to taste.
06 -
In a small bowl, mix together mayonnaise and hot sauce until well combined.
07 -
Spread the spicy mayonnaise on each tostada or warmed tortilla. Spoon the ceviche mixture into the center and top with sliced avocado. Serve immediately.