To prepare the fish, heat the oven to 200C/400F/Gas 6. Mix together the flour, chilli powder and some salt and pepper, and dust the fish in it, then shake off any excess. Heat a large, non-stick, ovenproof frying pan over a medium-high heat; use two frying pans if the fish are too large to fit in a single pan. (If you have no ovenproof pans, then preheat a lightly oiled baking tray.)
Add the oil and heat it until it hazes. Add the sole (skin-side down if you’ve part-skinned them) and fry, without moving them, for 3-4 minutes, or until they form a golden-brown crust. Turn over and transfer the frying pan to the top of the hot oven (or transfer the fish to the warmed baking tray and place in the oven), and cook for a further 8–10 minutes, or until cooked through and the flesh is opaque.
Meanwhile, bring a large pan of salted water to the boil, drop in the asparagus and simmer for three minutes, or until just tender. Remove from the water, drain and set aside.
For the sauce, melt the butter in a frying pan over a medium heat, and let it bubble for 2-3 minutes, or until it turns a nut-brown colour. Reduce the heat to low, add the ginger, lime juice, pomegranate seeds and chopped coriander and warm it through; don’t overheat it or it will separate. Season to taste. Serve the sole with the asparagus and spoon the sauce over the top.