Make the dressing by combining the vinegar, mustard and honey in a small food processor or blender and slowly, with the motor running, add the oil to create an emulsion. Set aside when blended.
Slice or form the chevre into 8 medallions (discs) about 1/2 inch thick. Coat each disc completely with bread crumbs, firmly pressing crumbs onto the cheese. In a large non-stick skillet, melt butter over medium heat, then gently add the goat cheese and sauté until golden, about 2 minutes on each side. Remove and drain on paper towels.
Core and chop the pears into bite-sized pieces. Add the spinach, arugula, pears and cranberries to a large bowl and toss with half the dressing. Divide the lettuce mixture onto four serving plates and top each with 2 medallions of goat cheese. Serve with remaining dressing on the side.