Just on the east side of Tioga, above Ellery Lake.
You can park at the lake, walk across the dam, and your approach is complete.
Faces northeast, so the snow will be there well into June.
The slope ramps up gently, so you can go as steep or not steep as you feel comfortable.
It is sometimes used for beginner snow-mountaineering instruction.
Here's some pictures:
Dave's idea is real good too.
(who hasn't skiied ellery yet...)