Ham and Cheese Sliders

My Grandma Precious passed this one along to me!

1/2  lb. butter 1 tsp. poppy seeds sm. onion, or half of a large onion 1 tsp. mustard poppy seed buns boiled ham swiss cheese   Melt the first 4 ingredients together Spread the butter mixture on both sides of the bun Top with ham and cheese Cover in foil Bake in 375 oven for 20-25 mins.   This receipe makes 6 sandwiches.