For the fennel and carrot casserole, steam fennel and carrots for about 5 minutes and let cool. Then mix with bacon, pastry rice and 1EL cheese sauce powder.
Season with salt and pepper, place in a buttered casserole dish. Mix sour cream with egg and the remaining cheese sauce powder and spread over the vegetables.
Bake at 180° for about 25 minutes, until the fennel-carrot casserole has a nice golden color.