1
Cut baguette in half lengthwise.
2
In bowl, mix butter and mustard; spread on cut sides of baguette. Layer ham and cheese on bottom half of baguette. Cover with top half of baguette.
3
Cut sandwich in half; place in panini grill or other contact grill. Press top of grill down to compress sandwich. Grill until cheese is melted and bread is lightly browned and crisp.