Rinse the quinoa under cold water in a fine mesh strainer. Place it in a pot with two cups of water or chicken broth. Bring to a boil, then reduce heat to low and cover. Simmer for about 15 minutes until liquid is absorbed. Let sit covered for five minutes before fluffing with a fork.

Season the chicken breasts with salt, pepper, and garlic powder. Heat a skillet over medium-high heat with olive oil. Cook chicken for 6 to 8 minutes per side until the internal temperature reaches 165°F. Let rest for five minutes before cutting into bite-sized cubes.

Chop all vegetables into uniform pieces. In a small bowl, whisk together olive oil, lemon juice, minced garlic, salt, and pepper to make the dressing.

In a large mixing bowl, combine fluffed quinoa, diced chicken, cucumbers, bell peppers, red onion, and parsley. Pour the dressing over and toss thoroughly. Gently fold in crumbled feta cheese. Taste and adjust seasoning if necessary.

Serve immediately or refrigerate for later use.