In a mixing bowl, whisk together olive oil, lemon juice, oregano, garlic powder, salt, and pepper.

Add chicken breasts to the marinade and let sit for at least 30 minutes.

Preheat the grill to medium-high heat and grill chicken for 6-7 minutes on each side or until cooked through.

In a saucepan, bring water to a boil and add quinoa. Reduce heat, cover, and simmer for 15 minutes until water is absorbed.

Fluff quinoa with a fork and let cool.

In a large bowl, combine cooled quinoa, cherry tomatoes, cucumber, red onion, parsley, and feta cheese.

Drizzle with lemon juice and olive oil, season with salt and pepper, and toss to combine.

In a bowl, mix the berries with honey and let sit for 10 minutes.

In serving glasses, layer Greek yogurt and the berry mixture.

Drizzle with vanilla extract and serve chilled.