Rinse 200 grams of quinoa thoroughly under running water to remove any bitterness. Drain well.
In a saucepan, bring 500 ml of water to a boil. Add the rinsed quinoa and a pinch of salt. Reduce the heat to low, cover, and let it simmer for 15-20 minutes or until the quinoa is cooked and the water is absorbed. Fluff the quinoa with a fork and let it cool.
In a large mixing bowl, combine the cooked quinoa with 1 chopped cucumber, 1 chopped tomato, 1 chopped onion, 1 chopped green bell pepper, and a handful of chopped coriander leaves.
In a separate small bowl, prepare the dressing by whisking together 2 tablespoons of lemon juice, 2 tablespoons of olive oil, 1 teaspoon of cumin powder, salt, and black pepper to taste.
Pour the dressing over the quinoa and vegetable mixture. Toss well to combine all the ingredients.
Refrigerate the salad for at least 30 minutes to allow the flavors to meld. Serve chilled.