Wake the zucchini, clean and cut in half lengthways. Carefully scoop out the zucchini halves with a spoon. The edge of the zucchini should be 5-10 mm thick everywhere.
Blanch the zucchini halves for 3 minutes and drain on a wire rack with the opening facing down.
Salt the zucchini chunks from the hollowing out well and drain them on a sieve.
Put the feta, zucchini chunks, garlic and chilli in a food processor and puree. Season to taste with vegetable stock and salt, add cornstarch to thicken and turn yellow with about 1/2 teaspoon turmeric.
Fill the zucchini halves with the mixture and place on an oiled tray.
Cook in the preheated oven for 20-30 minutes until the mixture is lightly browned.
If there is anything left over from the mixture, I use it to fill red pointed peppers that have been cut lengthways and cook them as well.