In a large bowl, add the ground turkey, spinach, sun-dried tomatoes, red onion, garlic, dill, mayo, Dijon, salt and black pepper. Gently mix with your hands to combine.
Divide the burger mixture into 4 patties. Cover and refrigerated for 30 minutes, or overnight.
Preheat oven to 400ºF.
Place the turkey burgers on ta sheet pan and drizzle with olive oil. Transfer to the oven and cook for 20-25 minutes
Slather buns with tzatziki sauce and garnish with toppings of choice. Enjoy!
Tzatziki Sauce:
Grate the cucumber and place in a strainer. Set aside for 30 minutes.
In a bowl, combine the drained cucumber, yogurt, garlic, lemon juice, fresh dill, kosher salt and ground black pepper and mix well. Cover and refrigerate for 30 minutes or up to 3 days.