Petit Croque Monsieur

Ingredients in this Recipe

1 tablespoon balsamic vinegar
1 teaspoon sugar
1/4 cup plus 2 tablespoons coarse whole grain mustard
24 very thin slices white sandwich bread, crusts removed
4 tablespoons unsalted butter
6 ripe but still firm Forelle or large Seckel pears, 2 chopped into 1/4 inch pieces, and 4 cut crosswise into 1/4 inch slices
8 ounces thinly sliced Gruyere cheese
8 ounces thinly sliced ham, preferably Black Forrest

See Full Recipe at Martha Stewart