1. Grate zucchini, season with salt and let sit for 5 minutes.
2. Meanwhile, heat a skillet over medium heat. Add frozen cauliflower rice to the skillet and let it defrost quickly while stirring for a few minutes.
3. Using paper towels or a clean kitchen towel, squeeze excess liquid from zucchini and cauliflower (the more you squeeze the crispier your fritters will be).
4. In a bowl, combine zucchini, cauliflower, beaten egg and tapioca starch. Season with garlic powder, salt and pepper (to taste).
5. Heat oil in a large skillet over medium-high heat. Add spoonfuls of the mixture (make fritters relatively small), flatten with a spatula. Cook for 2-3 minutes per side, until crispy. Best when served immediately.