Preheat oven to 325°F Trim fat to about 1/4 to 1/2 inch thickness. Place ham, fat side up, in a roasting pan and roast for 2 1/2 to 3 hours (10 minutes per pound) until internal temperature reaches 130°F Remove from oven.
Turn oven up to 425°F Pour apple cider (or broth or water) into pan to a depth of 1/2 inch. Score ham and brush top with mustard. Combine pineapple and sugar and spread over ham, pressing in with the back of a spoon. Return ham to oven and cook about 15 to 20 minutes until browned. Remove ham from oven and place on a cutting board to cool about 20 to 30 minutes.
Scrape bottom of roasting pan to remove any bits that were stuck during cooking. Pour into a quart measuring cup. Pour off any accumulated fat. Add chicken broth to make 2 cups. Strain cooking liquid into a saucepan and add molasses, brown sugar and mustard; Bring to a boil and season with salt and pepper. Combine cornstarch with 2 tablespoons of water; add to saucepan. Boil, while stirring, until thickened. Pour into a gravy boat and pass with the ham.