Wash the zucchini and cut off both ends. Grate it using a coarse cheese grater. (You don't need to remove the skin, but you can discard any that comes off during grating.)
Caution: Do not use a food processor instead of grating, as this will release too much juice. The food processor will chop it too finely and it will not have the right consistency.
Season the grated zucchini with salt. I sprinkled it with 3 level teaspoons of salt. Taste it at the end to see if it's enough for you. Keep in mind that the Parmesan cheese will make it a little saltier. Stir and set aside for 15 minutes. During this time, the zucchini will release its juice.
Preheat the oven to 180°C or 350°F, setting it to top and bottom heat with fan.
Squeeze the juice out of the zucchini and place it in a mixing bowl. Add the grated Parmesan cheese. Grate in some garlic. Season with ground black pepper. Add a whole egg. Finally, sprinkle with 30 g of flour and mix thoroughly. I usually taste it at this point to see if it's salty enough.
Line your baking tray with baking paper. Drizzle the baking paper with a teaspoon of olive oil. Use a brush to spread the olive oil so that it covers the areas where you will be placing the doughnuts.
Place 5 spoonfuls of the mixture onto the baking paper. Flatten them with a spoon. I like them thin. Use the spoon to shape them into somewhat round shapes.
Place in the preheated oven. It will be ready after 20-25 minutes of baking.