Tonight was egg night at school. This is one of the dishes we made: eggs stuffed with mushrooms and egg yolks. I was very pleasantly surprised by how good this was.
Ingredients (for six small servings):
3 eggs, hard boiled
1 shallot, finely chopped
4 white button mushrooms, finely chopped
Juice of 1/2 lemon
1-2 Tbsp butter
For Sauce Mornay:
1 Tbsp butter
1 Tbsp flour
1 cup milk
Salt and pepper
4 Tbsp Gruyere cheese, grated
1 egg yolk
First, hard boil the eggs. There are a few ways to do this so that the yolks don't turn green on their surface. At school the official procedure is to place eggs in a pot with enough cold water to cover them and then about an inch more because some will evaporate when you start to heat it. Bring the water (with the eggs in it) to a boil, and once it is boiling, lower your heat to a simmer and cook the eggs for 11 minutes. Take them out of the hot water and put them into ice water to cool them off. After a few minutes, tap the shell so that it cracks, and put them into cold water with their shell cracked. The water will seep in between the shell and the egg white and make it easier to peel the hard boiled eggs.
Next, prepare a mushroom duxelles. Chop your white mushrooms and shallot finely, so they are in pieces about 1/8" or 3/16" -- 1/4" is too large. When the mushrooms are chopped, put them in a bowl and squeeze the lemon juice into them and toss them. Melt the butter in a small pan, add the shallots, and cook over low to medium-low heat -- what you want is for the shallots to begin to soften, but not brown at all. (This is called "sweating" the shallots.) When the shallots have begun to turn a bit translucent, after about 3-4 minutes, add the mushrooms to the pan, and salt them. Cook over low heat until the mushrooms release their water into the pan and then the water evaporates and the mushrooms are soft. Remove the pan from the heat and set it aside.
At this point, preheat your oven. It doesn't really matter much what temperature -- 350 or so is fine.
Now, prepare your eggs. Peel them (remove the shells) if you haven't already, and cut them in half lengthwise. Remove the yolks, and set the egg white halves aside -- those are what you will be stuffing soon. Crush the yolks with a fork so that they end up in smaller pieces than your shallot and mushrooms, and add stir them into the shallot-mushroom mixture.
Then it's time to do your sauce. Start by getting one egg yolk ready in a small bowl. Next, melt the butter in a small saucepan, then stir the flour into it, and once it is smooth cook that mixture over low heat for about 3 minutes. Don't let it get too warm, or it'll start to brown. It should just barely have some foaming bubbles to it, and you'll need to stir it every minute or so to keep it from browning. This is a "white roux," perhaps the most standard of classical sauce thickeners. Now, with a whisk ready to go in one hand, and the milk already measured and sitting next to your stove, raise the heat on your roux to high, and while whisking (start whisking the roux by itself before you start to pour), pour in about a quarter of the milk, and whisk it to try to break up lumps that form. Then, still whisking (but not as urgently), add the rest of the milk. Bring it all the way to a boil, and then reduce the heat so that it doesn't foam up and overflow your pan (but it should still gently boil), and whisk it for about 30 seconds to a minute. It should thicken up into a saucelike consistency. At this point, you have one of the five classic "mother sauces" (these are a few basic sauces that serve as the starting point for almost any sauce in a western dish) called "Béchamel." (If you followed the same process but used a light stock, like chicken, vegetable, or fish stock, instead of the milk, you'd have another of the mother sauces, Velouté.)
Take a couple of spoons of the sauce and stir them into your mushroom and egg yolk mixture. You can do this to taste -- this mixture is going to be the stuffing for your eggs, so you want it solid enough that you can mound it up on top of the egg white halves and it won't run at all. Otherwise, how much sauce to stir into it is only a matter of what kind of texture you think you'll like.
Now start to transform your Béchamel sauce into Sauce Mornay. Stir about half of the cheese into the sauce. (At this point, if you were serious about your sauce, you would strain it, but for home cooking if you don't feel like it, you can skip straining. The price of skipping it is that your sauce will be a little bit pasty in texture, and may have small floury lumps in it.) In a separate small bowl, stir up the egg yolk, and then add one small spoon of your white sauce to the egg yolk and stir them together. This is called "tempering" the egg, and its purpose is to prevent the egg from curdling (scrambling) when you add it to the sauce, which you're about to do. Remove the white sauce from the heat.
While the white sauce cools a bit before you stir the egg into it, use a fork or spoon to stuff the mushroom and egg yolk mix into your egg white halves. Mound it up on the eggs so there is plenty of stuffing on top of each egg. Place the eggs onto something that can go in the oven -- a regular old dinner plate is fine.
Finally, stir the tempered egg yolk into the white sauce. Season it with a pinch of cayenne pepper and nutmeg, and then taste it and add salt until it tastes like a nice sauce. Spoon the sauce over the stuffed eggs. Top each egg with a bit of the remaining Gruyere cheese. Place them in the oven to thoroughly warm the eggs, stuffing, and sauce, and melt the cheese, for about 4 minutes or so. If you want to brown up the tops a bit, you can put them under a broiler for a short time.
Now that I've written this out, I realize that as usual, I've probably overestimated its simplicity in the view of the average home cook. I think of this as being a simple recipe, something you might throw together for friends on a whim. I guess that's why cooking school is not a bad place for me to be.
When I describe a recipe for a general audience, it takes a lot of words. (Soon, I plan to write a piece about why this is, including an idea I've been considering for a bit of a new kind of cookbook someday.) If I were to write this recipe for myself or another cook, it would be much shorter, something like this:
- Hard boil and peel 3 eggs.
- Prepare a mushroom duxelles using the mushrooms, shallot, and lemon.
- Halve the eggs lengthwise, set the whites aside, grate or mash the yolks, and add them to the duxelles.
- Make a Béchamel. Add a bit of Béchamel to the duxelles and yolks. Stir half the cheese into the Béchamel, and strain.
- Temper the egg yolk, and stir it into the sauce. Season the sauce with cayenne pepper, nutmeg and salt.
- Stuff the eggs with the duxelles and yolks, top with the sauce and remaining cheese, bake to heat through and melt the cheese.