Remove excess moisture. Add grated zucchini and grated sweet potato to a colander, add a pinch of sea salt, mixing through the zucchini and sweet potato. Let sit for at least 15 minutes, then squeeze out as much excess moisture as possible.
Prepare mixture. Add to a large bowl with the remaining ingredients (except the coconut oil), mixing thoroughly with a wooden spoon.
Cook fritters. Add 2 tablespoons of coconut oil to a medium fry pan on moderate heat. Using a soup spoon or ice cream scoop, scoop out a heaped spoon of the fritter mixture and place in the pan and flatten them a little. Place as many as you want in the fry pan, making sure the edges don't touch. (I made my fritters around 6-7cm diameter). Cook for a few minutes on each side, until lightly golden and place on wire rack (to ensure crispiness) or a plate, repeating until you use up all the fritter mixture. You may need to add more coconut oil in between batches.
If you want to keep them warm, then place the cooked fritters on baking sheet lined with baking paper in the oven until you have cooked all the fritters.