Whisk Dijon mustard, maple syrup, chicken broth, and rice vinegar together in a medium bowl.
Heat a large skillet over medium heat. Brush some of the mustard glaze onto one side of the ham steaks. Place glazed-side down in the skillet. Brush some glaze on top of the ham steaks. Cook, turning frequently and brushing on more glaze, until heated through and the glaze has thickened, about 10 minutes.
