For the truffle mash, place the cooked potatoes into a bowl. Add the butter and milk and mash until smooth. Season, to taste, with salt and white pepper. Set aside and keep warm until ready to serve.
For the scallops, drizzle the scallops with olive oil.
Heat a griddle pan or frying pan until very hot, then add the scallops. Cook for about 90 seconds on each side, or until just cooked through, then remove from the pan.
To serve, place a portion of the warm mashed potato onto each serving plate and drizzle over a few drops of truffle oil. Top with the seared scallops.
