Depends how much you want to spend! these will cost more than White Spot!!!!
On the East shore of the lake Hotel Eldorado has dining at the lakeshore marina, or a little further on you could try Summerhill Winery or on the otherside of the lake near Westbank Mission Hill Winery, both of these have great views of the lake. Beware Mission Hill is outdoor only so not possible in inclement weather.
All these locations are very popular so try to make a reservation, you should be able to find menus on line.
Trevor