Pat the shrimp dry and toss them with the kosher salt and freshly ground black pepper. Have the oil, aromatics, tomatoes, sauces, sugar, basil, and citrus ready beside the stove because the stir-frying moves quickly.

Heat 1 tablespoon of the oil in a large wok or skillet over medium-high heat. Add the shrimp in a single layer and stir-fry for about 1–2 minutes per side, just until pink and nearly cooked through, then transfer them to a plate.

Add the remaining tablespoon of oil to the pan. Stir-fry the sliced onion or shallots for 1–2 minutes, until they begin to soften while retaining a little bite.

Add the minced garlic and cook for about 30 seconds, stirring constantly. Stop as soon as the garlic smells fragrant so it does not become bitter.

Add the halved tomatoes, light soy sauce, optional fish sauce, and sugar. Toss frequently for 2–3 minutes, allowing the tomatoes to soften and release a little juice while keeping some of their shape.

Return the shrimp and any juices from the plate to the pan. Stir-fry for another 1–2 minutes, until the shrimp are fully opaque and cooked through to approximately 145°F/63°C.

Turn off the heat and fold in the torn basil leaves. Add the optional lime or lemon juice, taste, and adjust the salt only if needed because the soy sauce and fish sauce already provide savory seasoning.

Spoon the stir-fry over cooked white rice and serve immediately. Divide the tomatoes and shrimp evenly among four portions for the best presentation.