I made Nigella's Coq au Riesling (delicious) but it was very liquid indeed. I want to make it again but would prefer it to be more like a stew than a soup next time. Should I reduce the liquid, add some flour, or both?
Nigella's Coq Au Riesling (from NIGELLA EXPRESS) is a white wine version of coq au vin that uses chicken thighs instead of a whole, jointed chicken. The dish is cooked covered so you could just partially cover the pan and let the sauce reduce a little as it cooks, though you may need to turn the chicken thighs over halfway through to make sure that they cook evenly.
The other option would be to use flour to thicken the sauce and for this we would suggest using a beurre manie (which, when translated, means "kneaded butter"). This is a useful way to thicken a sauce at the end of the cooking time. To make the beurre manie mix together equal quantities of soft unsalted butter and plain (all-purpose) flour until you get a very thick paste. We suggest using a tablespoon each of the butter and flour. Remove the chicken to a plate and bring the sauce up to a simmer. Whisk the beurre manie in to the sauce a teaspoon at a time, letting the sauce simmer for a minute or two between each addition to see how thick the sauce becomes. Stop when the sauce has thickened to your liking and you may not need all of the beurre manie or you may need to make a little extra, it depends on how thick you want the sauce and the volume of liquid to be thickened. Return the chicken to the pan and simmer for 4-5 minutes more before serving. if you have made the Coq au Riesling in advance then reheat the dish until piping hot all of the way though before thickening using the beurre manie.