Gather the ingredients and dice spinach, red onion, and any toppings you'd like.
Combine feta, ground turkey, ranch packet, diced red onion, and spinach in a mixing bowl. Fold together and form 4 patties.
Grease a skillet and heat stove to med-high. Cook burgers for 4-5 minutes a side or until burgers are completely cooked
Add sliced cheese or more crumbled feta 1 minute before burgers are removed from heat
Broil sliced and oiled buns for 2-3 minutes. Add desired toppings and enjoy!