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