Squeeze the citrus juices into a non-reactive bowl. Add the garlic, shallot, jalapeño, tomatillo, and roots from the cilantro. Cover and chill for up to four hours, stirring periodically.
Slice the scallops as thinly as possible, creating uniform discs. Plate.
Strain the juice mixture through a fine sieve or chinoise. Spoon a little over each disc of scallop. Drizzle lightly with good extra virgin olive oil. Garnish with rough chopped cilantro leaf, or with the best looking plouches from the bunch.