Brine the Chicken: In a large bowl, whisk cold water and salt until dissolved. Add the zest and juice of one lemon, 3 tablespoons olive oil, 4 cloves minced garlic, dried oregano, and black pepper. Submerge the chicken breasts, cover, and refrigerate for 30 minutes to 2 hours.

Prepare the Tzatziki: Grate half of one English cucumber. Toss with a pinch of salt and let drain in a fine-mesh sieve for 15 minutes. Simultaneously, place the Greek yogurt in another sieve over a bowl to drain whey. After 15 minutes, squeeze the grated cucumber dry in a clean kitchen towel. Combine the thickened yogurt, squeezed cucumber, 1 minced garlic clove, 1 tablespoon olive oil, 1 tablespoon lemon juice, fresh dill, and salt and pepper to taste. Cover and chill.

Cook the Chicken: Preheat oven to 400°F (200°C). Remove chicken from brine and pat dry with paper towels. Heat the remaining 1 tablespoon of olive oil in an oven-safe skillet over medium-high heat. Sear chicken for 2-3 minutes per side until golden. Transfer the skillet to the oven and bake for 10-15 minutes, or until the internal temperature reaches 165°F (74°C). Let the chicken rest for 5 minutes before slicing.

Prepare Bowl Components: While the chicken cooks, dice the remaining English cucumber, halve the cherry tomatoes, and thinly slice the red onion. Cook quinoa or rice according to package directions if not already prepared.

Assemble with Strategy: Portion the cooked grain into meal prep containers. Add the sliced chicken. Place the diced cucumber, tomatoes, and red onion in a separate small container or compartment within your meal prep container. Store the tzatziki in its own small container. Add the Kalamata olives and crumbled feta to the main container with the grain and chicken.

Serve: Just before eating, combine all elements. Drizzle with a little extra virgin olive oil and a splash of red wine vinegar. Season with additional salt and pepper if desired, and garnish with fresh dill or oregano.