In a large bowl, mix olive oil, lemon juice, minced garlic, oregano, salt, and pepper. Add chicken breasts and coat well. Marinate for at least 30 minutes for maximum flavor infusion.

If grilling, preheat your grill over medium-high heat. For oven baking, set it to 400°F (200°C). Prepare your cooking surface with nonstick spray or oil.

While waiting for the grill or oven to heat up, halve your cherry tomatoes and toss them lightly in olive oil with salt and pepper.

Grill each side for about 6-7 minutes until cooked through; you want an internal temperature of 165°F (75°C). If using the oven, bake for approximately 25-30 minutes.

In the last few minutes of cooking time, sprinkle crumbled feta cheese on top of the chicken to let it melt slightly (if using).

Once cooked through and beautifully browned, remove from heat. Serve alongside roasted vegetables or a fresh salad for a complete meal.