Knead flour, 1/2 teaspoon salt, butter and 1 egg to a smooth dough. Wrap in foil and chill for about 30 minutes. Drain artichokes and olives. Peel onions and cut into slices.
Quarter the artichokes. Stir cheese, milk and 3 eggs until smooth. Season to taste with salt and pepper. Finely crumble the rolls to breadcrumbs. Roll out the dough on a floured work surface and line a greased, floured tart tin (26 cm Ø) with lift-off base.
Sprinkle the bottom with breadcrumbs. Layer artichokes, onions and olives in the mould. Pour egg milk over the pan and bake in a preheated oven (electric range: 175 °C/ convection oven: 150 °C/ gas: level 2) for 35-45 minutes until the egg milk has set.
Wash and drain the rocket. Remove the tart, let it cool down a bit if necessary and sprinkle with rocket.