French onion homity pie

The cook

1. 01

   Step 1LINE THE TIN

   Roll the pastry on a lightly floured surface to about 3 mm thick. Line a 24 cm metal loose-bottomed tart tin, at least 4 cm deep, easing the pastry into the corners without stretching it. Leave a little overhang, prick the base lightly and chill for at least 30 minutes while you get cooking.

2. 02

   Step 2LIGHT THE JOE

   Light lumpwood charcoal in the Kamado Joe and establish a modest fire. Set a cooking grate in the upper position without the heat deflectors and stabilise around 170–180°C with the lid closed. Put a heavy barbecue-safe frying pan on the grate to warm. You need gentle, controllable heat, not a roaring furnace.

3. 03

   Step 3TAKE THE ONIONS SLOWLY

   Add the butter, oil, onions and a good pinch of salt to the pan. Cook for 45–60 minutes, closing the barbecue lid between stirs and stirring every 5 minutes, more often towards the end. They should collapse into a sticky, deep-golden tangle. Add a splash of water whenever the pan catches; brown bits are lovely, black bits aren’t.

4. 04

   Step 4BUILD THE FRENCH ONION BIT

   Stir the garlic and thyme into the onions and cook for 2 minutes. Pour in the cider and scrape up the sticky bits. Simmer for 5–8 minutes until almost all the liquid has gone, then stir in the sherry vinegar and plenty of black pepper. Transfer to a large mixing bowl.

5. 05

   Step 5COOK THE POTATOES

   Place the potatoes in a barbecue-safe saucepan, cover with water and salt it well. Set over the direct heat and cover with a lid to bring to the boil, then simmer for 12–15 minutes until just tender. Allow roughly 25 minutes overall. Drain thoroughly and leave to steam-dry for 5 minutes. Keep the chunks intact; this isn’t mash.

6. 06

   Step 6SWITCH TO BAKING

   Using heatproof barbecue gloves and the proper lifting tools, fit both heat deflectors in the lower position and return the cooking grates above them. Stabilise the Joe at 190°C for indirect cooking. Keep a clear air gap between the deflectors and the tin; putting pastry straight onto a deflector is a fine way to burn its bottom.

7. 07

   Step 7BLIND-BAKE THE SHELL

   Line the chilled pastry with baking parchment and fill with ceramic baking beans. Set the tin on the grate, close the lid and bake for 20 minutes. Remove the parchment and beans, then bake for another 5–8 minutes until the base looks dry. Brush the inside lightly with beaten egg and bake for 2 minutes to seal it. Trim the overhanging pastry carefully.

8. 08

   Step 8PILE IN THE GOOD STUFF

   Fold the potatoes, cream, mustard, parsley, 80 g of the Cheddar and 50 g of the Gruyère into the onions. Taste and adjust the salt and pepper before filling the pastry shell. Spoon the mixture in without crushing the potatoes, then scatter over the remaining cheeses.

9. 09

   Step 9BAKE UNTIL BUBBLING

   Bake indirectly at 190°C for 35–45 minutes with the lid closed, until the filling is piping hot in the centre and the cheese is bubbling with deep-golden patches. Rotate the tin once if one side colours faster. If the pastry edges get ahead of the filling, shield just the edges with foil.

10. 10

    Step 10LET IT SETTLE

    Lift the pie out and rest it in its tin on a rack for 20 minutes. This lets the filling settle and keeps the pastry from collapsing when you cut it. Remove the tin carefully and serve in generous wedges. A sharp mustardy salad alongside cuts through all that glorious cheese.