1Drain the pineapple rings into a bowl so you keep the juice, then pat the ham steak dry with paper towels so it sears instead of steams.
2Melt the butter in a large skillet over medium-high heat. Lay in the ham steak and sear until browned at the edges, about 3 to 4 minutes per side. Move it to a plate.
3Lower the heat to medium and put the pineapple rings in the same skillet in a single layer. Cook until golden in spots, about 2 minutes per side, then slide them onto the plate with the ham.
4Pour 1/4 cup of the reserved pineapple juice into the skillet and scrape up the browned bits. Stir in the brown sugar and simmer until it turns syrupy and coats the back of a spoon, about 2 minutes.
5Return the ham and pineapple to the skillet and turn them once in the glaze to coat, about 1 minute. Slice the ham against the grain and serve with the pineapple on top and the pan syrup spooned over.