The name of this decorative slicing technique comes from the V-shaped beard worn by famed painter, Sir Anthony Vandyke (1599-1641).

Vandyking is often done with tomatoes.

Here's how:
With a sharp knife, slice the tomato in deep, clean V shapes right around its circumference. Cuts should go right into the centre of the tomato. (Season the cut tomato, sprinkle with grated cheese, grill and serve.)