This is a dish good enough to feed presidents, and that’s what it did when the chef Rick Bayless served it at a state dinner at the White House in 2010 for President Felipe Calderón of Mexico. The green hue comes from cilantro and parsley, and the recipe is similar to one in “Fiesta at Rick’s,” his cookbook published that same year.
In a food processor, combine chilies, garlic, cilantro, parsley, olive oil and salt. Process until nearly smooth. Cover the herb paste and refrigerate until needed.
03To finish ceviche: In a large bowl, whisk together the lime juice and 1/2 cup of herb paste. Add fish and cucumber, and stir to combine. Cover and refrigerate for 30 minutes (or up to an hour). Transfer remaining herb paste to a jar, cover with a film of oil, refrigerate and save for another use, like stirring into eggs or smearing on chicken before roasting or grilling.
04Taste and season with additional lime juice or salt as desired. Gently fold in most of the avocado, reserving a few cubes as a garnish. Line plates or cocktail glasses with lettuce leaves, and top with ceviche and remaining avocado.