Slice Rolls and make sandwiches(Ham & Cheese) . Place in 9X13 pan (tighter the better - 4 across and 5 deep . You should have 4 -6 rolls left over
Mix together the butter, poppy seeds, sauce, mustard,onion . It does not have to be heated. Spoon over each sandwich. Cover with foil and bake 20-30 min in 350 oven . To Double use 2 13X 9 pans with 3 packages rolls . If you have 2 in the oven you might wish to increase your heat to 375 for 20-30 min.