Eat them right away or put them in a lunch box next day.
Peel the potatoes and the carrots. Grate them into a bowl.
Add zucchini, onion, flour, salt, parsley and egg yolks into a bowl. Stir to combine.
Place egg whites into a bowl and beat until stiff peaks form. Fold through the vegetable mixture.
Heat a large pan over medium heat. Add a little oil.
Add 1/3 of the mixture and cook for 5 minutes. Cook 4 at a time.
Turn and cook a further 5-8 minutes and repeat until all the mixture is cooked.