Definitely places up at Mt. Pinos, skiing from either direction from the parking lot up top, assuming the road's been plowed that far.
If not, last winter I tooled around on XC skis up near Charlton Flats and found a couple decent, open slopes, that's assuming ACH is open. Just across the road is Mt. Mooney, which is pretty gently angled and may have some open areas to practice.
I'd probably be up there myself but my skis are up at a cabin the So. Sierras.