8 slices challah bread, about 1/2-inch thick, toasted, or grilled
6 ounces Brie cheese, sliced
4 cooked chicken breast halves, sliced into thin strips
1 Granny Smith apple
In a small saucepan, whisk together vinegar, mustard and honey. Set pan over medium-high heat and bring to a simmer. Simmer until liquid reduces to 1/4 cup, about 3 minutes.
Spread mixture on toasted or grilled challah bread slices Top with Brie and then chicken. Using a vegetable peeler, shave apple into thin slices and arrange over chicken. Top with second slice of bread.