Recipe for three root gratin

Preparation:

Preheat the oven to 180°C (350°F).
Peel the beetroot, parsnips and sweet potatoes. Slice thinly using a mandolin or a sharp knife.
Rub the garlic cloves into a gratin dish and then grease generously with
butter. In a saucepan, combine the cream and milk. Add a pinch of nutmeg, salt and pepper. Heat over a low heat without boiling.
Arrange a layer of beetroot slices on the bottom of the dish, then a layer of parsnips and finally a layer of sweet potatoes. Repeat until all the vegetables are used.