Grate the carrot, zucchini, and onion using a grater or julienne peeler.

In a bowl, mix the grated vegetables with egg whites.

Season the mixture with salt and pepper to taste.

Heat a non-stick frypan over medium heat.

Place approximately 2 tablespoons of the vegetable mixture into the heated frypan.

Flatten the mixture slightly to form a burger about 1cm thick.

Cook the veggie burgers on one side until golden brown.

Flip the burgers and cook the other side until golden brown and crispy.

Serve immediately.