Thoroughly mix all ingredients for sauce in a bowl and let rest for 20-30 minutes.
Combine all ingredients except oil in a bowl. Toss and mix so that all the shrimp are thoroughly coated in the marinating ingredients. Let sit of 3-5 minutes.
Heat oil in a wok or large frying pan on high heat. Add shrimps and marinade and stir-fry on high heat. Shrimp should be cooked through and slightly browned - about 3 minutes.
Line a serving plate with lettuce leaves and trnsfer the shrimp onto the lettuce. Top with red pepper strips and cilantro. Garnish with tomato and cucumber slices. Offer Lemon Sauce in a small bowl alongside.