Mint - planted 3 seasons ago, weathers over nicely without anything special being done. Can be invasive if not contained. A lovely addition to both sweet and savory dishes. Our favorite is to add in cucumber salad with sour cream dressing and into Raita with yogurt and garlic.
Sage - planted the first year we built the raised beds, comes back annually but does have to be cut back because it can get woody. I trimmed it aggressively earlier this year and now it's thriving! Very prominent flavor so little goes a long way - great to add under the skin of roasted poultry like chicken, turkey and pheasant. Makes a very nice compound butter.
Thyme - has to be planted annually in our region because it can't weather over the snow and freezing temps even covered up. Light, fragrant, lemony herb which is nice in vinaigrette, pasta salads and added to pretty much any potato dish.