Preheat oven to 425 °. Melt the butter in a saucepan, add flour and cook over low heat, continuously mixing with a wire whisk 2 min. Gradually stir in cold milk, while whisking. Cook 5 minutes over low heat, stirring occasionally.
Break the eggs, separating the yolks from the whites. Combine the 6 egg whites in a bowl. Remove the butter-flour mixture from the heat, cut the blue cheese into pieces and add. Mix vigorously. Add the egg yolks, stirring immediately to prevent them from cooking. Beat the egg whites with a pinch of salt until stiff. Stir one fourth of the whites into the butter-flour mixture until it relaxes. Then, add the remaining egg whites, mixing gently.
Fill the molds up to two-thirds and bake about 10 min.
- For the soufflés to rise well, without bending, the molds must be buttered, preferably using a kitchen brush, then floured evenly. Turn the mold upside down and tap to get rid of excess flour. When filling the dough, be careful that the preparation does not drip over the edges.