Wash the zucchini and rub dry. Cut off the upper quarter as a lid and put aside. Hollow out the zucchini with a spoon. Season inside with salt and pepper. Put the zucchini lid back on.
Bake in the preheated oven (electric cooker: 150 °C/ convection oven: 125 °C/ gas: see manufacturer) for approx. 20 minutes, then allow to cool.
Bring the stock to the boil, pour over the couscous and let it simmer covered for about 10 minutes. Coarsely chop the olives. Cut feta cheese into approx. 1 x 1 cm small cubes. Peel and halve the onion and cut into fine cubes.
Wash mint, shake dry. Pluck off leaves and chop finely, except for something to garnish. Mix feta, onion, mint and olives with couscous. Season salad with Ras el-Hanout, salt and pepper.
Stuff the zucchini with the salad. Arrange on plates and garnish with mint.