This is a lovely baked dish for winter and fills the house with yummy aromas while baking. You can make a plain dauphinoise with only potatoes, or try other vegetables in place of the fennel: celeriac, onion, sweet potato and squash all make great gratin dishes.
If you are watching your waistline you can make this dish with just stock but adjust the cooking times, it will take longer to cook with the stock probably 40-50 minutes. It does not freeze well made with stock
To Freeze: Cook to point 4, simmer and cook over a very gentle heat, stirring occasionally for 15-20 minutes or until the potatoes feel half cooked. Stir in half the parmesan, transfer to a large ovenproof dish. Cool cover with foil, label and freeze To reheat cook from frozen, uncover and put the baking dish in the baking oven, on the bottom set of runners in an Aga for approx 1 - 1 ¼ hours until golden and bubbling. For conventional cooking preheat the oven to 180°C / 350°F / gas mark 4. Uncover and put the baking dish in the oven and bake 1-1 ½ hours or until soft when poked with a knife, golden and bubbling.