If the shrimp are frozen, place them in a bowl of cold water for a few minutes until fully thawed, then drain well. If cooking raw shrimp, simmer them briefly in salted water just until they turn pink and opaque, then immediately drain and let them cool. Pat the shrimp completely dry with paper towels so excess moisture doesn’t water down the salad.
Wash the cucumbers thoroughly and slice them thinly into rounds or half-moons, depending on your preference. Thin slices give the best crunch and absorb the dressing evenly. Peel and thinly slice the onion as well, keeping the pieces light and delicate so they add flavor without overpowering the salad.
In a small bowl, add the olive oil, fresh lemon juice, mustard, minced garlic, salt, and black pepper. Whisk until the dressing looks smooth and slightly creamy, with the oil fully emulsified into the lemon juice. Taste and adjust seasoning if needed before adding it to the salad.
Add the dried shrimp, sliced cucumbers, and onions to a large mixing bowl. Spread everything out slightly so the ingredients are evenly distributed before dressing.
Pour the dressing over the shrimp and vegetables, then gently toss using a spoon or clean hands. Move slowly and carefully so the shrimp stay intact and the cucumbers remain crisp, making sure everything is evenly coated.
Cover the bowl and place it in the refrigerator for 10–15 minutes. This short chill allows the flavors to come together without softening the vegetables too much. Serve cold for the freshest taste and best texture.