Grate the zucchini and place in a colander. Sprinkle with 1/2 tsp salt and let sit for 15 minutes with a weight on top to help release moisture. Then squeeze out as much liquid as possible.
In a mixing bowl, combine grated zucchini, drained ricotta, parmesan, chopped spring onion, flour, minced garlic (if using), chopped mint, egg, nutmeg, black pepper, and 1/4 tsp salt. Mix until well combined.
Heat olive oil in a frying pan over medium heat.
Lightly oil your hands and form spoonfuls of the mixture into flattened fritters. Place gently into the hot oil.
Cook for 3–4 minutes per side or until golden and crispy. Avoid overcrowding the pan.
Transfer to a plate lined with paper towels to drain excess oil. Serve warm or at room temperature.