Potato Cups with Mushrooms and Shallots

1. Preheat the oven to 375 °F.
2. Prick the russet potatoes with a fork and cook them in the microwave on High until the potatoes are very soft and a knife can easily slide into them.
3. Remove the potatoes from the microwave. Scoop out the flesh and using a ricer, squeeze the potatoes into a mixing bowl. Add the softened butter, egg yolks, salt, pepper, and nutmeg. Using a spatula stir the potatoes until all the ingredients are thoroughly combined. Spoon the mixture into a piping bag with a star tip.
4. On a parchment-lined baking sheet, pipe a circle about 3 inches in diameter. Pipe the potatoes to fill in the circle and then pipe 3 layers on top of the circle to form a cup. Repeat with the remaining potato mixture. You should have 4 potato cups.
5. Mix the remaining egg with 1 Tablespoon water in a small bowl and use a pastry brush to lightly brush the cups with the egg wash.
6. Bake them for 10 to 12 minutes, until the edges are golden and the potatoes have firmed.

Potato, mushroom and shallot mixture

1. While the russet potatoes are cooking, bring a small saucepan of water to a boil. Add the Peewee potatoes and cook for 10 minutes until the potatoes are tender. Drain and rinse with cold water to stop the cooking. Set aside.
2. In a medium sauté pan, melt the butter over medium heat. Add the shallots, mushrooms, salt, pepper, and nutmeg. Cook until the shallots are very soft and the mushrooms and tender. Add the potatoes and cook for 5 minutes. Add the marsala and thyme and cook for 3 minutes or until almost all the liquid evaporates.
3. Stir in the creme fraiche and stir until incorporated. Taste and adjust the seasonings. Add the parsley and stir. Divide the potato and mushroom mixture among the potato cups.