Instructions

  1. Brush one side of bread slices lightly with oil. Brush other side of bread slices with honey mustard. Top the mustard side of four of the slices with cheese. Top cheese with cucumber, spinach, and red onion. Top with remaining bread slices, mustard sides down.
  2. Preheat an indoor electric grill or a large skillet over medium heat. Place the sandwiches on the grill rack. If using a covered grill, close lid. Grill sandwiches until bread is golden and cheese is melted. (For a covered grill, allow 3 to 5 minutes. For an uncovered grill or skillet, allow 6 to 8 minutes, turning once halfway through grilling.) With a long serrated knife, cut sandwiches in half.
  3. Meanwhile, in a medium saucepan stir together soup, tomato, and balsamic vinegar. Heat through. Serve soup with sandwiches.