Step 1

Spray 6- to 7-quart oval slow cooker with cooking spray. Make cuts about 1 inch apart and 1/4 inch deep in diamond pattern in top of ham. Place ham in slow cooker.

Step 2

In small bowl, stir together mustard, syrup and brown sugar with whisk until well blended. Pour mixture over ham.

Step 3

Cover; cook on Low heat setting 3 to 4 hours or until meat thermometer inserted in ham reads 140°F.

Step 4

Remove ham from slow cooker. Cover loosely with foil; let stand 10 to 15 minutes. Strain cooking juices. Slice ham; pour strained juices over ham.