Preheat oven to 400* F. Place the chocolate and the butter in a mixing bowl over a pan of simmering water. Do not allow mixing bowl to touch the water as your chocolate will scorch. (You can also use a bain marie or double boiler.) Stir until melted. Remove from heat.
In another mixing bowl mix the eggs, sugar, water, flour, and vanilla until just mixed. In a thin, steady stream add the melted chocolate/butter mixture. Stir until fully combined.
Pour mixture into 4 one-cup ramekins. Place on a baking sheet and onto the middle rack in oven.
Bake 13-15 minutes, or until the edges are fully set. Remove from oven immediately. Dust with powdered sugar. Serve with cream, berries, or ice cream.