Spread one side of each bread slice with butter and the other with half the Russian dressing.

Top two dressing sides with pastrami and Swiss and set the other slices nearby.

Griddle bread-side down over medium-low heat until crisp and the cheese melts, covering briefly if needed.

Remove from the pan, add drained coleslaw and the remaining dressing to the pastrami halves.

Close the sandwiches, cut in half and serve immediately.