Greek Burger with Tzatziki Sauce - Oryana

Ingredients

• 1 lb ground beef
• 1/3 cup feta cheese, crumbled
• ½ teaspoon oregano
• sea salt and black pepper to taste
• 4 hamburger buns
• lettuce
• sliced tomato
• sliced red onion
• 1 6 oz. container plain yogurt
• ½ cup cucumber, peeled, diced small
• 1 teaspoon chopped fresh mint or ½ teaspoon dried
• sea salt to taste