Step 1: Prepare and Marinate the Chicken

1. Prepare the Chicken Breasts: Place the chicken breasts between two pieces of plastic wrap or in a large zip-top bag. Using a meat mallet or a heavy rolling pin, gently pound the chicken until it is an even thickness of about ¾-inch. This is the single most important step for ensuring the chicken grills evenly and stays juicy. Thicker parts take longer to cook, often resulting in the thinner parts becoming dry.
2. Create the Marinade: In a medium-sized bowl, whisk together the ¼ cup of olive oil, fresh lemon juice, lemon zest, minced garlic, dried oregano, chopped parsley, smoked paprika, 1 teaspoon of sea salt, and ½ teaspoon of black pepper. Mix until everything is well combined.
3. Marinate the Chicken: Place the pounded chicken breasts in a large zip-top bag or a shallow glass dish. Pour the marinade over the chicken, ensuring every piece is fully coated. Seal the bag (removing as much air as possible) or cover the dish. Let the chicken marinate in the refrigerator for at least 30 minutes. For best results, marinate for 2-4 hours. Do not marinate for more than 6-8 hours, as the acidity from the lemon juice can start to break down the chicken’s texture, making it mushy.

Step 2: Cook the Quinoa

1. Rinse the Quinoa: This is a non-negotiable step! Place the 1 cup of uncooked quinoa in a fine-mesh sieve. Rinse it thoroughly under cold running water for about a minute, swishing it around with your fingers. This removes the natural coating called saponin, which can give the quinoa a bitter or soapy taste.
2. Toast the Quinoa (Optional but Recommended): Heat 1 teaspoon of olive oil in a medium saucepan over medium heat. Add the rinsed and drained quinoa to the pot. Toast for 1-2 minutes, stirring constantly, until the quinoa is fragrant and makes a slight popping sound. This step enhances its natural nutty flavor.
3. Cook: Pour in the 2 cups of water or chicken broth and the ½ teaspoon of salt. Bring the liquid to a rolling boil.
4. Simmer: Once boiling, immediately reduce the heat to the lowest setting, cover the saucepan with a tight-fitting lid, and let it simmer for 15 minutes. It’s important not to lift the lid during this time, as the steam is essential for cooking the grains.
5. Rest and Fluff: After 15 minutes, remove the saucepan from the heat but leave the lid on. Let it stand, covered, for an additional 5 minutes. This allows the quinoa to absorb any remaining moisture and finish steaming. After 5 minutes, remove the lid and use a fork to gently fluff the quinoa. You’ll know it’s perfectly cooked when the grains are tender and the tiny “germ” ring has separated from the seed.

Step 3: Grill the Chicken

1. Preheat the Grill: Preheat your outdoor grill or indoor grill pan to medium-high heat (around 400-450°F or 200-230°C). Clean the grates well and lightly oil them with a paper towel dipped in a high-smoke-point oil (like canola or avocado oil) to prevent the chicken from sticking.
2. Grill the Chicken: Remove the chicken from the marinade and let any excess drip off. Place the chicken breasts on the hot grill. Cook for 5-7 minutes per side. The exact time will depend on the thickness of your chicken. Avoid the temptation to press down on the chicken with a spatula, as this squeezes out the juices.
3. Check for Doneness: The most reliable way to check for doneness is with an instant-read meat thermometer. The chicken is cooked through and safe to eat when the internal temperature in the thickest part reaches 165°F (74°C). The juices should also run clear if pierced.
4. Rest the Chicken: This step is just as important as cooking! Once cooked, transfer the grilled chicken to a clean cutting board. Let it rest for 5-10 minutes before slicing. This allows the juices to redistribute throughout the meat, resulting in a much more tender and flavorful piece of chicken. If you slice it immediately, all those delicious juices will run out onto the cutting board.

Step 4: Assemble the Bowls

1. Slice the Chicken: After resting, slice the chicken against the grain into ½-inch thick strips.
2. Build Your Bowl: Divide the fluffed quinoa among four bowls. Top with the sliced grilled chicken.
3. Add Vegetables and Garnish: Arrange the halved cherry tomatoes, diced cucumber, and sliced red onion around the chicken. Sprinkle with crumbled feta cheese and a final garnish of fresh parsley or mint. Serve immediately.