Spinach & Herb Turkey Burgers with Portobello "Buns"

This low-carb burger replaces the typical bun with roasted portobello mushroom caps. Creamy tzatziki and crisp sliced red onion add texture and flavor to this easy Greek-inspired burger recipe.

Ingreadient

  • 1 pound lean ground turkey
  • 1 cup frozen chopped spinach, thawed and squeezed dry
  • ⅓ cup kalamata olives, chopped
  • 1 ½ teaspoons lemon zest
  • 1 teaspoon garlic powder
  • ½ teaspoon dried oregano
  • ¾ teaspoon salt, divided
  • ½ teaspoon ground pepper, divided
  • 2 tablespoons extra-virgin olive oil
  • 8 large portobello mushrooms, stems removed (see tip)
  • 4 tablespoons tzatziki
  • 1 cup arugula
  • 8 (1/4 inch thick) rings red onion