Ingredients
- 2 Tbsp extra-virgin olive oil, divided, plus olive oil cooking spray
- 1⁄2 cup finely chopped onion
- 5 oz baby spinach
- Kosher salt and freshly ground black pepper
- 1⁄4 cup plain nonfat Greek yogurt
- 1⁄4 cup low-fat mayonnaise
- 2 Tbsp minced seeded pepperoncini
- 1 Tbsp liquid from the pepperoncini jar
- 1 to 2 tsp fresh lemon juice or to taste
- 1 tsp minced garlic
- 3 oz crumbled feta cheese
- 2 Tbsp chopped fresh oregano
- 1 lb ground turkey
- 4 whole-wheat hamburger buns, toasted
- Lettuce and sliced tomatoes for garnish
