We offer this special dish (by advance reservation only) on Sunday morning of the Kennett Square Mushroom Festival and occasionally during the year. All the preparation, except the final heating and assembly, is done the night before. There is a good deal of work involved, but it is well worth the effort for a very special breakfast or brunch.
For EACH serving:
Poach 2 eggs. As they are done, put them in ice water to stop the cooking. When all the eggs are done gently add some ice to the water, cover, and store in the refrigerator over night. (We suggest adding 1-2 T. white or apple cider vinegar to the poaching water, and gently pre-boiling the eggs for 10 seconds immediately before cracking and poaching.)
Take a large handful of fresh baby spinach leaves, put them in a colander in the sink, and blanch them by pouring a good amount of boiling water over them. Let drain. If the spinach seems too wet, give it a gentle squeeze or two over the colander. Store in a covered bowl in the refrigerator.
Brush the bottom of a 4-5 inch Portobello mushroom with oil, place gill-side up on a rimmed baking sheet covered with foil or parchment, and roast in a pre-heated 325 degree oven until the mushrooms just begin to release their liquid. Remove from the oven, cool, and store covered in the refrigerator. (Drain and save any liquid that might be in the mushroom caps, as well as any liquid in the baking sheet. Add this to the liquids when making the sauce.)
Then make the porcini mushroom sauce. You will need about 3 T. of sauce per serving (We suggest you make extra, because it is also wonderful over pasta, chicken, and meat.) This recipe makes about 1-1/2 cups of sauce. The final color of the sauce will depend on the stock or broth that you use, and how much you brown the flour.
Soak in hot water until very soft _ c. (or more to taste) dried porcini mushrooms. You may need to add additional warm water as they swell. Remove the mushrooms from the soaking bowl, and squeeze them in your hand over the bowl to capture the liquid. Chop the mushrooms finely, discarding any really tough stem parts, and sauté them for a few minutes in butter. Return the cooked porcinis to the soaking bowl.
Finely chop 2 shallots (a small onion or a leek (white part) can be substituted). Cook gently in 4 T. butter, for 1 minute. Add 4 T. all purpose flour, and cook over medium heat, stirring often, for at least 3 minutes. Continue cooking and stirring for a few minutes until the flour begins to color, but do not let the shallots/onion/leek burn. Whisk in slowly 2 c. stock or broth (we use a rich Inn-made veal stock, but you can use any beef, chicken or vegetable stock that is low sodium), the porcinis and the reserved porcini soaking liquid and any liquid saved from roasting the mushrooms. Grind in some fresh pepper (white preferred) to taste. Add a bay leaf or two, and a stem or two of parsley (Italian flat preferred), and 1 whole clove. Bring just to a boil over medium-high heat, stirring often. Then lower the heat and gently simmer, stirring frequently, until the sauce thickens enough to coat the back of a spoon (or perhaps a bit more). Remove from the heat and discard the bay leaves, parsley, and clove. Pour into a bowl and let cool (stir a few times to keep a skin from forming). Cover and refrigerate.
Final assembly in the morning:
Pre-heat the oven to 200 degrees and warm the mushrooms and spinach.
Bring a pot of water to a boil, then reduce the heat to a very gentle simmer. The size of the pot will depend on how many poached eggs you need to re-heat at one time.
Gently warm the sauce on the stove or in a microwave. Do not boil.
Re-heat the eggs in the simmering water for 2-3 minutes.
Place a warm mushroom in the center of a plate.
Spread a layer of warm spinach over the mushroom cap.
Put 2 poached eggs on each mushroom (putting them on a paper towel to drain first is recommended).
Top with about 3 T of sauce (be sure to stir each time so that each serving gets some of the chopped porcinis and shallots).
Notes: We serve the mushrooms with toast, bacon, and a pan-roasted tomato half. Instead of bacon, you can put a slice of grilled/fried ham or Canadian bacon on the mushroom before adding the spinach. You can also use smaller Portobello mushrooms, and put one egg on each.