Place bacon in a hot skillet over low heat. Cook completely to render fat. Remove lardons from skillet and reserve on paper towels. From the skillet remove 2 tablespoons of rendered fat to a bowl. Add shallots to fat. Stir in mustard and vinegar. Season with salt and pepper. Whisk in oil until dressing is emulsified.
Toss chicory pieces with bacon, vinaigrette and croutons.