1 lb raw shrimp, cleaned, deveined, washed and cut in half vertically
1 cup lime juice (about 3 – 4 limes; save the zest)
¼ cup lemon juice (about 2 lemons; save the zest)
Lime zest from juiced limes
Lemon zest from juiced lemons
1 small red onion, thinly sliced
1 cup ice water
1 Tbsp white vinegar
½ cup citrus juice reserved from cooking shrimp
1 Tbsp fish sauce
1 Tbsp Worcestershire sauce
1/2 tsp agave syrup
2 cloves garlic, minced
½ bunch cilantro, separated whole leaves and minced stems
1 jalapeño pepper, deseeded and minced
2 serrano peppers, one deseeded and minced; one sliced very thin
2 Tbsp Extra Virgin Olive Oil
1 cucumber, peeled and cubed roughly ¼ inch
1 avocado, cubed roughly ¼ inch
4 small radishes, sliced very thin
1 serrano chili, sliced very thin
1 Tbsp gochugaru (Korean chili flakes)
Kosher salt to taste
8 corn tostadas
1. In a medium bowl, cover the shrimp with lemon and lime juice, adding more than recipe calls for if necessary. Allow the shrimp to marinate in the citrus until they turn slightly pink, about 30 minutes. Season with salt to taste. Once the shrimp is pink, strain off the citrus juice into a bowl and reserve the juice and shrimp separately.
2. In a small bowl, combine the ice water and vinegar and submerge the sliced red onion. Set aside and allow to soak.
3. To make the aguachile, place ½ cup citrus juice, garlic, fish sauce, Worcestershire sauce, agave, cilantro stems, jalapeño, scallion and serrano in a blender. Purée just until smooth. Add salt to taste and olive oil and purée until emulsified.
4. Pour the aguachile over the shrimp and refrigerate for at least 30 minutes.
Remove the shrimp from the fridge and gently fold in the avocado and cucumber. Taste and make any last adjustments to seasoning with salt and more reserved citrus juice if desired. Remove the red onions from the water and drain well. Garnish the aguachile with the onions, sliced radish, cilantro leaves, sliced serrano and gochugaru. Serve immediately with the tostadas on the side and your favorite Mexican hot sauce.