Cook and stir onion and pepper in hot oil in a skillet over medium-high heat, uncovered, for 7 minutes or until onion turns brown. Remove onion; set aside. Add beans to skillet; cook 1 minute. Add wine or broth and thyme; reduce heat and simmer, uncovered, 3 to 4 minutes or until liquid is reduced by half. Mash beans slightly.
Spread bread shells with bean mixture; top with onion. Bake in a 450 degree F oven for 8 to 10 minutes. Cut into wedges. Garnish with red pepper and marjoram, if desired. Makes 16 servings.