Add all ingredients together in a large bowl and stir well to mix.
Form into 5 large burger patties.
For the BBQ: Preheat grill to medium-high. Place burgers on top rack, close lid and grill 15 minutes one side or until browned. Close lid and grill another 7–10 minutes or until a thermometer set in centre of burgers registers 165°F (74°C).
In the oven: Bake at 425°F for 20 minutes, then flip and cook for 20 minutes on the other side or until a thermometer set in the centre of burgers reaches 165°F (74°C).
Serve in hamburger buns with your favorite burger toppings like tomatoes, mayonnaise, etc.
Recipe by Moms & Munchkins at https://www.momsandmunchkins.ca/spinach-feta-burgers/