We like trying a new spin on potatoes every once in a while, and this random discovery was an all-round hit. In some ways it's similar to Duphinoise potatoes, but a lot richer. It does take a lot more preparation though, but if you have the time, the effort is worth it.
Cube and boil potatoes in salted water for a few minutes. They should be slightly tender but not too soft.
Saute a couple of diced shallots and minced garlic in butter until tender.
Stir in a spoonful of flour and cook for a minute, stirring to stop it catching on the pan. Stir in a couple of cups of chicken stock then cream to make a moderately thick sauce. Simmer for a few minutes stirring constantly.
Stir in a generous handful of cheese, a squirt of mustard, and season with salt and pepper. Finally stir in the drained potatoes.
Spread the mixture into a greased baking pan and bake for up to an hour. Sprinkle another handful of grated cheese and chopped chives or green onions on top and either return to bake or put under the grill to brown.
