Cook the vegetables in a saucepan for about 10 minutes.
Line the bottom of the baking dish with hash browns. Take the vegetables out of the water and spread over the hash browns. (Still keep water). Chop the Cabanossi and add them as well.
Now mix the hollandaise sauce with the cream and 4 - 5 ladles of vegetable water in a saucepan. Season with the stock cube, salt, pepper and the herbs of Provence. Now distribute the sauce evenly in the baking dish.
Bake the casserole for 30 minutes at 180 ° C fan oven.