Dice the onion making the cuts as small as you can.
Grate the zucchini.
Combine all of the ingredients into a bowl and mix until well incorporated.
Form into patties, the size of your choice.
Grill on a preheated grill until cooked to 160℉, or heat a pan with olive oil and saute them on both sides until cooked.
Serve them with Tzatziki sauce.
Notes
I divide my burgers in 3 patties not four. It's just a personal preference to have a slightly larger burger. You can add the condiments of your choice but I love Tzatziki Sauce! I don't always eat this with a bun and it's wonderful on it's own for lunch. Once the burgers are cooked and cooled, you can store them in the refrigerator in an airtight container for 2-3 days. Reheat them on the grill over low heat or in the microwave. You can freeze these burgers either raw or cooked. To freeze them raw, prepare the patties and separate them between layers of parchment paper before placing them in a plastic bag. For cooked patties, separate the patties with parchment so that they don’t stick to each other. When you need the burgers, let them thaw in the refrigerator overnight and cook them fully or reheat them.