Mix the pineapple, brown sugar and mustard in glass bowl. Stir well and microwave on medium high about 2 minutes. Stir. If sugar is not fully dissolved then return to microwave and heat one minute at a time, stirring, until the sugar has dissolved.

Spray the inside of your slow cooker with cooking spray.

Make thin cuts in the ham a few inches deep. Place ham in the slow cooker and brush the top and all sides generously with the glaze. You want some of the glaze to seep down into the slices you have cut.

Cook on low 3-4 hours until ham is heated through. Brush the glaze over the ham and sides periodically during the cooking process.

Slice and serve with more of the sauce from the slow cooker.

Variation: If using your oven cook ham, with ¼ inch of water in the bottom of the roaster, at 325 degrees about 15 minutes per pound. Brush glaze over ham starting 40 minutes before the end of the cooking time. Brush generously every 10 minutes.