jerusalem artichoke + potato {gratin}

Last weekend it finally stopped raining. Bright blue skies and full days of sun. While I was busy inside, working away on the final touches of my book, Domenico decided to head up to Umbria to work on the vegetable garden for the day.

Sadly, for me, there was nothing left for him to harvest. We’d cut the last of the cabbages and cauliflower weeks before, and the straggling leaves of kale and Swiss chard looked a bit done for. But Domenico wasn’t too upset. He’s just as happy getting the rototiller going and turning over the earth for the spring planting.

So while I was back in Rome, in my office, trying to concentrate on commas and captions, of course all I could think about was Domenico out digging in the garden. And then my mind, as it does tend to do, started to wander.

I started thinking of all the things I wanted to plant this year: heirloom varieties of tomatoes, bright cosmos in different colors, purple radishes, corn…and soon enough I was ‘just taking a little break’ from writing, to peruse online seed catalogs.

Of course the first thing to catch my eye was a bright yellow page full of sunflowers. At least that’s what I thought it was at first. When I started reading the description I realized that these were Jerusalem artichokes. “Yes!” I thought, making a mental note to buy some roots at the nursery. “I’ve been meaning to plant these for years.”

And then “Hey, wait! We did plant them!” What had happened to our carefully tended patch of Jerusalem artichokes?

The previous May Domenico had carefully planted about a dozen small tubers in the hope they would multiply over the summer and fall. We’d done it in the past, and had moderate success. This past summer they burst into bloom, as they do, looking like sunflowers. And then died down.

After which, we completely forgot about them.

I prayed that Domenico hadn’t gotten the rototiller going yet.

As it turns out the rototiller was out of gas, and so happily our little crop of Jerusalem artichokes was completely in tact, where it had been sleeping below ground for the last few months, waiting for Domenico to dig them up.

I’m not sure if it was due to the abundant rain, or the fact that we left them on their own for so long, but this year’s crop was bigger than any I remembered from past years. The tubers themselves were massive, and there were dozens.

I don’t know why these knobbly vegetables aren’t more popular. Their nutty taste is delicious, and they work well in any dish where you would normally use potatoes but don’t want the starch. I often use them in soups, but my go to recipe is simply to steam them, sprinkle with cheese and pop them under the broiler for a few minutes. Kind of poor man’s gratin.

But these beauties were so big and beautiful I decided to treat them as they deserved: with cream and butter and all sort of good things. A rich man’s gratin.

I found a lot of gratin recipes online, and this one is a mish mash of various ideas, with some of my own additions. The idea of using oats came from Hugh Fernley-Whittingstall, which allowed me to use up that one measly quarter cup of oatmeal in the pantry.

In the past, when I’ve made the poor mans version of this, I’ve always served it as a side dish. But this recipe, with the cream, nuts and cheese, is definitely main course material.

jerusalem artichoke + potato gratin

1/2 pound / 300 grams jerusalem artichokes, trimmed and sliced
1/2 pound/ 300 grams potatoes, peeled and sliced
2 tablespoons butter
salt
2 onions
6 stalks celery, chopped
4 cloves garlic
4 sprigs of thyme
1/4 cup white wine
1 cup heavy cream
1 cup vegetable stock

Topping:
4 slices of stale bread, ripped into bit sized pieces
1/2 cup oatmeal
1/4 cup roughly chopped toasted hazelnuts
1/4 cup melted butter
1/2 cup grated cheese (I used cheddar)

Preheat the oven to 180C/ 350F

Place the butter in a frying pan and add the onions, the garlic, celery and thyme and about a half tsp of salt. Let this cook for about 10 minutes, on low heat, until it’s softened.

Add the potatoes and artichokes, which should be sliced into about 1/4 inch slices. Stir and let cook for a few minutes. Add the white wine, and let evaporate. Add the cream and stock and let simmer for another 10 minutes or so. The cream and stock should start to thicken a bit.

In the meantime mix the topping ingredients in a small bowl.

Turn out the contents of the frying pan into a buttered oven proof dish. Spread the topping on top. Place in oven for about a half hour, until the topping starts to turn golden.

One word of warning: if you’ve never eaten Jerusalem artichokes, they can have a rather explosive effect. That’s why I usually mix things up, using equal amounts of artichokes and potatoes and – in this case – onions and celery. But feel free to use what ever other vegetables you’d like. And of course, let me know if you do.