1/4 c. (1/2 stick) butter
6 leeks (white & pale green parts only), sliced
2 lg. onions, cut into eighths
8 shallots, halved
2 garlic cloves, minced
1 1/2 (10 oz.) bags frozen baby onions, thawed, drained
2 c. whipping cream
2 tbsp. dry bread crumbs
2 tbsp. chopped fresh parsley

Melt butter in heavy large skillet over medium heat. Add leeks, large onions, shallots and garlic and saute until all are tender, about 20 minutes. Add baby onions and cook 10 minutes longer, stirring occasionally. Mix in 2 cups whipping cream. Boil until cream is thickened to sauce consistency, about 10 minutes. Transfer vegetable cream mixture to 6 cup shallow baking dish. (Can be prepared 1 day ahead. Cover and refrigerate. Return mixture to room temperature before continuing.)

Preheat oven to 425 degrees. Sprinkle bread crumbs over onion mixture. Bake until bread crumbs are golden brown and onion mixture bubbles, about 20 minutes. Sprinkle with parsley.