Peel the celery and cut off 8 large slices. Blanch the celery slices in boiling salted water, let them drip off, spread with mustard and cover with the cold cuts. Wash the parsley, remove the leaves and spread on the cold cuts. Peel carrots and cut them into long sticks. Put carrot sticks on the celery slices, roll them up and stick them with wooden skewers. Cook the rolls in broth for about 8 minutes, take them out and keep the vegetable broth.
Melt the fat, sweat the flour in it, deglaze with the vegetable stock and milk while stirring. Let simmer for about 3 minutes and season with salt and pepper. Put the rolls into one large or 4 small casseroles. Spread the sauce over them. Bake in the preheated oven (electric cooker: 200 °C/ convection oven: 175 °C/ gas: level 3) for approx. 10 minutes. Remove and serve garnished with pink berries and parsley