To make Marcela Valladolid’s shrimp ceviche, peel 1 pound of medium-size raw shrimp. Remove the tails and veins, and cut the shrimp into thin pieces. Place the shrimp into a large bowl, and add toss them with 1/2 cup of freshly squeezed lime juice. Leave the shrimp to sit in the juice for exactly 15 minutes. Allowing the shrimp to sit for longer can result in a tougher texture, and less time can result in underprepared shrimp.
Peel, seed and finely chop 1 cup of cucumber and 1 cup of tomato. Seed, devein and finely mince 1 serrano chile pepper. You can add an additional pepper if you prefer a spicier ceviche. Add these ingredients to a second mixing bowl, and combine them with 1/2 cup of freshly squeezed lime juice, 1/2 cup of chopped fresh cilantro and 1/2 cup of finely chopped red onion.
Toss the vegetables until they are evenly distributed, and then add the vegetables to the bowl of shrimp. Toss all the ingredients until the shrimp is evenly distributed as well. Season the ceviche with salt to taste. Serve the dish chilled or at room temperature on saltine crackers with hot sauce, and garnish with lime wedges. This dish serves four to six people.