Four porcelain bowls souffle or custard cups with a capacity of 300 ml was smeared with butter and sprinkled with breadcrumbs, and excess shakes. 30 g butter fry until it begins to foam, put the flour and stir for 2 minutes on the stove (if you get the crumbs - this is not a problem). Then the vessel is removed from the heat and add half the milk. Stir mixture until smooth and gradually add the remaining milk. Returns to the fire and stir until the mixture boil and thickened. Remove from heat, add cheese and mustard and stir until smooth mixture. The eggs were divided into white and yolk. Add egg yolks one at a time with stirring to the mixture, then season with salt and pepper to taste. Whip of snow (to form a soft-tipped) and added with gentle stirring to cheese mixture. The mixture is stirred gently to not fall egg whites. Pour into bowls, bake for 15 minutes in a preheated 200 ° C oven, or until golden. Serve immediately. * If your bowls are smaller can use more numbers, or use other forms.