At last I got to try the Sunday brunch at Amelys Restaurant at Le Royal in Luxembourg City. All I can say is that the selection was fabulous!
In addition to the huge cold buffet, we got to choose between meat and fish (hot dish) and we picked the latter. There was also more hot food that we could have ordered at a counter but we had already eaten so much. The dessert buffet was a delight as well. Unfortunately I didn't take a photo and I can't show you.
I would say that it is the best brunch in the City together with the one at IKKI, except that the setting and the service at Amelys are much better. I also found the complimentary on-site parking very useful. See more photos of Amelys in my post here.