Preheat the grill to its highest setting.
Pour the cracked black peppercorns onto a plate. Press one side of each of the goats' cheese rounds into the peppercorns.
Place the goats' cheese rounds onto the bread rounds, peppered-side up and place under the grill for four minutes, or until the cheese is soft and melted.
For the Cumberland sauce, melt the butter in a frying pan over a medium heat. Add the shallots and the ginger and fry for 2-3 minutes, until soft.
Add the port and boil until the liquid reduces to a very thick syrup, then add the stock.
Bring the stock to the boil, then add the redcurrant jelly and the green peppercorns and reduce the heat to simmer for 2-3 minutes, or until the jelly has completely dissolved.
To serve, place the cheese on toast onto a warmed plate. Drizzle the sauce over the cheese and sprinkle with pickled walnuts.
