Trim the ham roast as needed to fit inside the inner pot. (I purchased a 10 pound ham and cut it in half.) Add 1 1/2 cups water to the pot. Place the trivet in the pot and put the ham on top.
Close and lock the lid. Turn the steam release valve to closed. Press Steam and set time for 8-10 minutes. (There's some leeway because the ham is already cooked-you're just heating it up. Go with less time if your cut is smaller, more if you have a larger cut with thick slices.)
When the timer is done, do a quick release and set the ham aside on a broiling pan to be glazed. If the ham isn't sliced already, score it so the glaze will run down into the ham and get caught in little "puddles" on top of the ham roast.
For the glaze
Place all the ingredients in a small saucepan and bring to a boil. Add more water as needed to get the consistency you want.
Boil for 1 minute, stirring regularly. Pour the glaze over the cooked ham.
Broil on High for 1-3 minutes until the glaze is bubbling and crackling. Watch carefully-sugar will burn quickly!
Remove from heat and serve immediately.
If using an uncut ham, addition cook time may be needed (up to 20 minutes)Other flavors (pineapple, etc.) can be added by wrapping ham in foil and cooking