Jerusalem artichokes are gnarly, awkward, puzzling little tubers, with a tendency to play up. But, they’re also one of the tastiest roots around. Here, I’m roasting them with thyme, onions and garlic before baking them in a crumbly pastry case alongside dark, iron-y cavolo nero kale and chunks of ripe, soft blue cheese, all bound together in a rich custard. Serve warm from the oven or cold the following day.
For the pastry:
200g (7oz) Plain Flour
100g (3½oz) Unsalted Butter
Good pinch of fine sea salt
About 75ml (2¼fl oz) Chilled Water
For the filling:
1 Small Bunch of Cavolo Nero
350g (12oz) Jerusalem Artichokes
1 Onion, sliced
3 Garlic Cloves, sliced
2 Thyme Sprigs, leaves picked
2tbsp Extra-Virgin Olive Oil
100g (3½oz) Blue Cheese (or your Favorite cheese)
For the custard:
150ml (5fl oz) Double Cream
150ml (5fl oz) Whole Milk
1 Egg Yolk
Heat the oven to 180°C/160°C fan/350°F/gas mark 4.
First, make the pastry. Pulse the flour, butter and salt in a food processor to the consistency of breadcrumbs. With the motor running, steadily add the water, stopping as soon as the dough comes together. Remove the dough, knead it a couple of times, then wrap it in parchment and chill it in the fridge for at least 30 minutes.
Bring a pan of water to the boil. Strip the cavolo nero leaves from the coarser, thicker stalks, rinse briefly, then blanch in the boiling water for 2–3 minutes, or until tender. Drain thoroughly. Once cool enough to handle, squeeze out the excess water and roughly chop. Set aside for later.
Scrub the artichokes, peel off any thick skin and cut them into manageable pieces. I like to keep mine in longer lengths, but it doesn’t really matter.
Place the artichokes in a roasting tin with the onion, garlic, thyme and olive oil. Season well with salt and pepper and roast for 35–60 minutes, until softened. (The variation in cooking times depends on the age, size and variety of the artichokes.) Stir at least twice during cooking, so that the artichoke pieces cook as evenly as possible.
While the artichokes are cooking, bake the pastry case. Roll the chilled dough into a thin round large enough to line a 24cm (9½in) loosebottomed, fluted tart tin, with an overhang. Prick the base, then line it with baking parchment and baking beans. Bake ‘blind’ for 20 minutes, then remove the beans and parchment and return the pastry case to the oven for a further 5 minutes, or until the base is dry and lightly colored. Remove from the oven and trim the overhang. Set aside.
Make the custard. Put the cream, milk, eggs and egg yolk in a bowl, season, then mix.