Season the Dover soles with salt and white pepper. Dip on both sides into flour and then pat off the excess. Heat the oil in a large well-seasoned or non-stick frying pan. Add one of the soles, lower the heat slightly and add a small piece of the butter. Fry over a moderate heat for 4–5 minutes, without moving, until richly golden. Carefully turn the fish over and cook for a further 4–5 minutes until golden brown and cooked through. Lift on to a serving plate and keep warm. Repeat with the second fish. Remove the bones as described in my Rick Stein's Fish & Shellfish video skills guide. Discard the frying oil and wipe the pan clean. Add the remaining butter and allow it to melt over a moderate heat. When the butter starts to smell nutty and turn light brown, add the lemon juice, parsley and some seasoning. Pour some of this beurre noisette over each fish and serve with the lemon wedges.