Feta and spinach not only add great flavor to these Greek-inspired burgers, but also provide moisture and texture to lean ground bison. The yogurt sauce is a perfect condiment, with much less fat than regular mayonnaise.

Ingredients

• 1 pound ground bison
• 1/2 cup cooked spinach, squeezed dry
• 1/2 cup crumbled feta cheese, preferably sheep's-milk
• 2 teaspoons chopped fresh dill
• 1 teaspoon chopped fresh oregano
• 1 teaspoon ground cumin
• 1 teaspoon minced garlic
• 3/4 teaspoon kosher salt
• 1/2 teaspoon freshly ground pepper
• 3/4 cup nonfat or low-fat Greek-style plain yogurt , (see Note)
• 1 teaspoon freshly grated lemon zest
• 2 teaspoons lemon juice
• 1 teaspoon chopped fresh dill
• 1 teaspoon chopped fresh mint
• Pinch of kosher salt
• Freshly ground pepper , to taste
• 4 French rolls, or 4-inch pieces of baguette, preferably whole-wheat, split and toasted
• 16 thin slices English cucumber
• 8 slices vine-ripened tomato
• 4 thin round slices red onion

Directions

• Preheat grill to medium-high.
• Place bison, spinach, feta, 2 teaspoons dill, oregano, cumin, garlic, 3/4 teaspoon salt and 1/2 teaspoon pepper in a large mixing bowl. Gently combine without overmixing. Form into 4 oval-shaped patties roughly the size of the rolls.
• Oil the grill rack (see Tip, below). Grill the burgers until an instant-read thermometer inserted into the center registers 155 degrees F, 5 to 6 minutes per side.
• To prepare yogurt sauce: Combine yogurt, lemon zest and juice, 1 teaspoon dill and mint in a small bowl. Season with a pinch of salt and pepper.
• Assemble the burgers on rolls with the yogurt sauce, cucumber, tomato and onion.

Tips:

• Note: Greek-style yogurt is made by removing the whey from cultured milk, which gives the yogurt an extra-thick and creamy texture. Look for it with other yogurt in large supermarkets.
• Tip: To oil a grill rack, oil a folded paper towel, hold it with tongs and rub it over the rack. (Do not use cooking spray on a hot grill.)