This goes excellently with pretty much anything... and is equally fantastic when sneaked cold from the fridge on the following day.
For six.
Ingredients: 1 kg Potatoes (something like Maris Piper is fine); 6 medium Shallots; 2 large Garlic cloves; generous pinch of grated Nutmeg; 1 tsp dried Thyme; 8 fl oz Milk; 8 fl oz Cream; 2 tsp Salt; Pepper, half a dozen grinds of the mill; 2 tablespoons of Butter.
Method:
1. Heat the oven to 150 degrees C.
2. Peel the Potatoes and slice them finely, either (carefully) by hand or by using a mandoline. Put the slices immediately to soak in a large bowl of cold water, and leave them soaking while you prep the shallots and garlic.
3. Peel and finely chop both the Shallots and the Garlic; mix them together in a small bowl, along with the Nutmeg, Thyme, Salt & Pepper.
4. Drain the Potato slices into a colander (shake it to remove as much excess water as possible), and arrange a third of them in a layer to cover the bottom of a buttered baking dish. Cover this layer with half of the Sallot-Garlic mixture....then another layer of Potates, then the remainder of the Shallot-Garlic mixture, and finally a last layer of Potato.
5. Combine the Milk & Cream in a jug, and pour it over the top layer of Potato slices. Dice the Butter and scatter it over the top of the gratin. Bake in the pre-heated oven for two hours (and if you don't want to serve it immediately, it can then hold in an oven at 100 degrees C for a further hour, and will come to no harm).