Chicken, mushroom and tarragon ragout

Method

1. Add 2 tbsp of the oil to a large, heavy-based frying pan over a medium-high heat. Season the chicken pieces well with salt and pepper. Add them, skin-side down, to the pan and brown all over (you may have to work in batches to avoid overcrowding the pan), transferring to a large, heavy-based casserole as you go.
2. Add the shallots to the pan, cut-side down, and cook them just long enough to caramelise the cut side. Add them to the casserole with the chicken.
3. Add another 2 tbsp oil to the frying pan, then tip in the mushrooms and a good pinch of salt. Fry until they release their liquid and begin to take on some colour – you give the final dish a lot more flavour this way. Add them to the casserole.
4. Lower the heat to low-medium, add the final 1 tbsp oil, then toss in the onions, thyme, bay and a generous pinch of salt. Cook the onions, stirring from time to time, until very soft. This will take about 20 minutes. Add the celery and cook for a few more minutes.
5. If you’re using cognac/brandy, add it to the pan, let it warm slightly, then carefully light it with a long match or a barbecue lighter. When the flames die down, pour in the wine and simmer for 5 minutes. Pour in the stock and simmer for a further 10 minutes. Taste and season with salt and pepper, then pour the contents of the pan into the casserole.
6. Add the carrots, turnips and celeriac to the casserole, give everything a good stir, then put the casserole over a medium heat. Bring to a bare simmer, then partially cover and cook gently for 1 hour, stirring halfway through, until the chicken is very tender. Add the parsley and tarragon, then check the seasoning before serving.