In a medium bowl, whisk together Greek yogurt, olive oil, fresh lemon juice, lemon zest, minced garlic, dried oregano, salt, black pepper, and optional ground cumin until smooth.

Coat the chicken tenders in the marinade, cover with plastic wrap, and refrigerate for at least 1 hour.

Preheat your grill to medium-high heat (about 400°F) or your oven to 400°F (200°C).

For grilling, place the chicken tenders on the grill and cook for 3-4 minutes per side.

For baking, arrange on a prepared baking sheet and bake for 18-20 minutes, flipping halfway.

Let the cooked tenders rest for 3-5 minutes before serving.

Garnish with parsley or dill and serve with pita bread, Greek salad, or tzatziki.