Prepare Your Work Area You will make a water bath ( bain marie ) for the royale custard. You need two baking pans to bake the royale. One can be a heat proof teacup or a flat form which fits inside the second pan. The second, larger pan will hold hot water for baking the custard so it does not curdle.
Turn on the oven to 300°F. Boil several cups of water for the water bath.
Generously butter your form (can be a tea cup, a ramekin or a small casserole dish), line with a piece of wax paper cut to fit the bottom and butter that too.
Make the "Eierstich" - Royale Heat the milk or cream in a small pan to just below the boiling point.
Beat the egg, egg yolks, nutmeg and salt together.
While whisking constantly, pour the hot milk in a thin stream into the eggs.
Let the foam, if any, settle. Pour through a fine sieve into your form. The sieve collecst any cooked egg or bits of large nutmeg. Try not to let the foam flow on top as it forms a disagreeable crust which you must remove after baking.
Place the larger dish in the oven, then your custard dish inside. Pour hot water around the outside about 2/3 of the way up the form.
Bake for 20 - 30 minutes (depends on how thick your royale is) or until set.
Let the royale cool for 20 minutes or more (you may also refrigerate), then unmold onto a cutting surface by loosening the sides of the custard with a knife and the gently sliding or flipping the custard out of the form.
If you used a flat form, you can cut the royale immediately into fancy shapes such as diamonds. You may also use a cookie cutter.
If you baked the royale in a teacup or smaller form, you must cut the custard into quarter or half inch layers with a knife and use the individual layers to cut fancy shapes. ( See example )
Tips on Making Royale You may color your "Eierstich" for fun (since it is used in clear soup) with a teaspoon of tomato paste for red or finely minced parsley for green. You may also use other fresh herbs, but filter through a sieve before baking because the pieces rise to the top of the "Eierstich."
To serve, place several pieces in the bottom of a soup plate, pour hot broth over it and garnish with herbs as desired. Serve at once.
Do not cook the royale in the broth because it cannot take much handling and the broth will become cloudy.
A good "Eierstich" is known for its smooth, velvety texture, which is a bit like soft tofu. If the water in the water bath comes to a boil in the oven the royale will become porous and if you beat air into it before it is baked the same thing could happen.
Other methods for cooking "Eierstich" include cooking it in a zip top plastic bag in a water bath, cooking it in simmering water on the stove top and cooking it in a double boiler method over the potato pan. None of these guarantee a smooth product but are less complicated.
The egg to yolk ratio usually cited is one extra yolk per egg. The more milk you add, the softer the royale (harder to handle). Some "Eierstich" recipes contain no milk or cream, or just a little. Experiment until it works for you.