Preheat oven to 400 degrees. Generously spray a mini muffin tin with non stick cooking spray and set aside. Melt chocolate and butter in a large bowl. Cool 3 minutes. Stir in eggs and egg yolks until incorporated. Stir in powdered sugar and flour. Spoon into prepared muffin tin so batter is 3/4 of the way up. Bake 4-7 minutes or until the edges are cooked and the centers are soft. Cool 5 minutes and carefully remove from pan using a butter knife. Serve warm with vanilla ice cream.