Rinse the cooked shrimp under running water and drain well. If frozen, thaw completely in the refrigerator before use.

Prepare 2 tbsp of minced garlic. For better texture and aroma, coarsely chop fresh garlic with a knife instead of using pre-minced garlic.

Heat vegetable oil in a pan over low heat. Add minced garlic and chopped green onion, and sauté slowly to create aromatic oil.

Once the green onion turns golden and the aroma is infused into the oil, add the shrimp and stir-fry over medium heat. For a spicier flavor, add chopped chili peppers.

When the shrimp is golden, add ketchup, soy sauce, sugar, chili powder, vinegar, and water. Stir-fry over high heat until the sauce thickens. Adjust the seasoning to taste.