Right now it is a tie between California Vintage Wine Bistro & Stone Groove Stillhouse (both in Anaheim.)
I consider them both 'nice' places so we're definitely not there as often as we like but they're great!
California Wine Bistro in Anaheim! Great wine bar and delicious food.
Also Tikiyaki in Orange. I went for the first time last week thanks to this sub, worth every penny!