Cut the pears into quarters, removing the core from each quarter.
Bring the water, pear juice concentrate, ginger and lemon juice to a simmer in a large pan.
Drop in the pear quarters, cover the pan and simmer very slowly until the pears are tender (the time will vary, so allow 20-45 minutes to be safe).
Meanwhile, dry roast the oats and walnuts in a frying pan over a moderate heat and warm the honey in a small pan.
Serve the pears with the oat and walnut mixture on top, and a spoonful of fromage blanc and drizzle over the warmed honey.