There are so many ways to make a gratin. You can use any kind or combination of root vegetable (winter squash, mushrooms and artichokes are also good). Traditionally a gratin is topped with parmesan or gruyere cheese, but any delicious, aged, hard cheese will work. I am currently in love with Midnight Moon aged goat gouda which can be acquired at Stinky Brooklyn on Smith Street. You can use milk, creme, bechamel sauce or even just a flavourful stock as the binder.
A couple of years ago I was studying puppetry in France for five weeks. I was very broke so I didn’t eat out (I know tragic). My apartment only had a toaster oven and I mostly ate tiny gratins that I made from the ridiculously good local creme and vegetables. When I do not have access to superior local creme I prefer milk or bechamel sauce. I love that a gratin, along with a salad or simple cooked green vegetable, is a complete and satisfying meal.
Celeriac is also known as celery root and it is very, very ugly. I strongly encourage you to try it, despite it’s troll like appearance. It has a lovely mild celery flavour and a nice texture. This gratin will leave you with some leftover milk that has been thickened by the potato and flavoured by the leek, fennel and celeriac. It is delicious! Save it to make broccoli soup or savory corn pudding!
- 4 garlic clove (one crushed and three thinly sliced)
- butter for the pan
- 1 fennel bulb sliced very thin (greens reserved for another use)
- 1 celeriac knob (trim the ugly outer knarls off and and discard. Slice the heart very thin)
- Russet potatoes peeled and sliced very thin (enough to make 3 lbs total fennel, celeriac and potato)
- One quart of milk
- 1 bay leaf
- a few sprigs of fresh thyme or a few pinches of dry
- white part of 2 large leeks (greens reserved for another use) halved, thoroughly washed and sliced very thin.
- salt and white pepper
- 1 or 2 cups cheese (did I mention the Midnight Moon aged goat gouda?)
- 2 Tablespoons butter
- Preheat the oven to 375 degrees.
- Rub a 9″x 12″ gratin dish with the crushed garlic clove and then slather the dish with butter.
- Place the rest of the garlic along with fennel, celeriac, potatoes, milk, bay leaf, thyme, leeks and salt in a pot. Bring to a boil and cook until the potatoes are barely tender. If you sliced everything thinly enough this takes almost no time. Drain and reserve the milk.
- Make a single layer of vegetables in the bottom of the gratin, season with pepper and then sprinkle lightly with cheese. Repeat this until all of the vegetables and cheese are used up, ending with a layer of cheese on top.
- Gently pour some of the milk over the gratin so that comes up to the top layer of vegetables. Save the rest of the milk in the fridge for another recipe.
- Dot the top of the gratin with the butter and bake until a golden crust forms on the top (about an hour).