Start by peeling and deveining the shrimp, then pat them dry with paper towels to remove excess moisture.
Place the shrimp in a bowl and pour the freshly squeezed lime juice over them, ensuring they are fully submerged.
Allow the shrimp to marinate in the lime juice for about 15-20 minutes, until the flesh turns firm and slightly opaque, with a bright appearance.
While the shrimp are marinating, thinly slice the red onion and chop the cilantro; set aside.
Finely dice the jalapeño, removing seeds if you prefer milder heat, and add it to the bowl with the marinated shrimp.
After marinating, drain the shrimp briefly if there’s excess lime juice, then gently fold in the sliced red onion, chopped cilantro, and diced tomatoes.
Give everything a gentle toss to combine, ensuring the flavors meld without breaking the shrimp apart.
Refrigerate the ceviche for about 10-15 minutes to chill and allow the flavors to deepen.
Serve the shrimp ceviche cold, garnished with additional cilantro or lime wedges if desired, and enjoy the bright, tangy flavors with that satisfying firm bite of the shrimp.
