From "Eat Greek for a Week", by Tonia Buxton. I like to use diced chicken breast so it doesn't matter if the number of breasts I use matches the number of diners. Skinless boneless thighs would be a great (and much undervalued) substitute in this kind of dish. I replaced the butter beans with baby sweet corn knowing that the butter beans wouldn't go down well with my daughter. I was surprised to see Tonia suggests 2 tablespoons of mustard for the sauce! I wasn't brave enough for that and used less than half and it seemed to work out, but of course it would depend upon how strong the mustard is.
One mans journey of culinary discovery aided greatly by popular cookery writers