Turkey Spanakopita Burger

Name: Turkey Spanakopita Burger
Ingredients: 2 tablespoons olive oil (divided use); 1 cup chopped onion (red or yellow is fine); 2-4 garlic cloves, pressed or minced; 1 (6- to 8-ounce) package fresh baby spinach; 1 pound ground turkey (93% or 99% lean is fine); 1 teaspoon dried oregano; 15 grinds black pepper; 1/2 teaspoon paprika; 1/4 teaspoon ground coriander (optional if you don't have it); Pinch dried thyme; Pinch crushed red pepper flakes; 12-20 pitted Kalamata olives, quartered; 1/4 pound feta cheese, crumbled