Only two weeks after we had these for Rose's birthday, here is the recipe at long last. These are from The Children's Quick and Easy Cookbook by Angela Wilkes. It's a DK book so you know that means plenty of big pictures. These were a snap.
4 ounces fine dark chocolate.
Preheat oven to 400 degrees. Break the chocolate into a bowl. Melt it over a saucepan of simmering water, stirring until smooth. (I melted it in the microwave.) Remove chocolate from heat.
Butter for greasing ramekins (I used custard cups)
Scant 1/2 cup of superfine sugar (this can be found near the coffee and tea under the name quick dissolving sugar)
Grease four ramekins lightly and sprinkle with a little of the sugar.
Separate the eggs into two bowls. Stir the rest of the superfine sugar (from Step 2) and four egg yolks into the melted chocolate. (I just now noticed that you were supposed to use four instead of five egg yolks ... turned out just fine with five.)
Whisk all five egg whites with a pinch of salt until they form stiff peaks. Then fold them gently into the chocolate.
Fill the ramekins until nearly full. Bake for 15 minutes until they rise and puff up. (I put the ramekins on a baking sheet so they wouldn't tip over.) Sprinkle with confectioners' sugar if you like (I didn't).