In a large bowl or resealable bag, combine the boneless, skinless chicken breasts with minced garlic, extra virgin olive oil, fresh lemon juice, dried oregano, salt, and pepper. Mix well until the chicken is evenly coated in the marinade. Seal the bag or cover the bowl, and refrigerate for at least 1 hour, preferably overnight.

If you're grilling, preheat your grill to medium-high heat, around 375°F. For baking, set your oven to 400°F (200°C) and prepare a greased baking dish.

In a small bowl, mix plain Greek yogurt with grated cucumber, seasoning it to taste with salt and pepper. Stir until well combined.

Cook the marinated chicken on the preheated grill for 5-7 minutes per side, or until they are golden brown and their internal temperature reaches 165°F. If baking, arrange the chicken in your prepared dish and cook in the oven for 20-25 minutes.

Once cooked, remove the chicken from the grill or oven, letting it rest briefly before serving. Plate your Greek Chicken Tenders and drizzle generously with the creamy yogurt sauce.