Grate the zucchini using the large holes of a box grater into a colander. Toss with 1 teaspoon salt and let sit for 15 minutes to draw out excess moisture.

Squeeze the grated zucchini firmly in a clean kitchen towel or cheesecloth, wringing out as much liquid as possible. This step is crucial for crispy fritters.

Transfer the squeezed zucchini to a large mixing bowl. Add the crumbled feta, spring onions, fresh dill, and fresh mint. Toss to combine.

Add the beaten eggs, flour, baking powder, black pepper, and nutmeg to the bowl. Mix well until a thick batter forms that holds together.

Heat the olive oil in a large non-stick frying pan over medium heat until shimmering, approximately 170°C if using a thermometer.

Working in batches, drop heaped tablespoons of the mixture into the hot oil, gently flattening each fritter with the back of the spoon to about 1cm thickness.

Fry for 3-4 minutes per side until deep golden brown and cooked through. The fritters should be crisp on the outside and tender within.

Transfer cooked fritters to a plate lined with paper towels to drain excess oil. Continue with remaining batter, adjusting heat as needed.

Serve the kolokithokeftedes warm, arranged on a platter with lemon wedges and tzatziki on the side for dipping.