I'm hoping you other curry-heads also have this same experience some time. You really really want a ruby, but all you have in the cupboard is a jar of curry sauce.
What have you done to bring a curry jar to life?

This evening, all I have is a jar of Sharwoods's tikka massala. I'll add half a diced red onion, four garlic cloves and a little green chili to begin with, then add the chicken for 5 mins and then the sauce, and stir in some chopped koriander to finish just before serving. It works ok, and tastes a whole lot better than the sauce would without the additions!
But what are you experiences?