14 ounces wild mushrooms, like oyster, crimini or porcini
3 tablespoons butter, divided
4 shallots, peeled and sliced
½ teaspoon minced garlic
1 teaspoon champagne vinegar
2 tablespoons destemmed and chopped fresh rosemary
6 ounces gruyere cheese, shredded
Salt and pepper to taste
1 egg, whisked
Flaked sea salt for finishing
Slice the mushrooms into thin slices. Melt two tablespoons of butter in a large saucepan. Sauté the sliced mushrooms until they start to darken and release their juices, about 4 minutes. Transfer the mushrooms to a plate lined with paper towel and pat dry.
In the same saucepan, heat one tablespoon of butter on high heat. Sauté the shallots and garlic until softened, 3-5 minutes. Immediately before the shallots start to brown, add champagne vinegar and rosemary and stir until absorbed. Remove from heat and let cool.
Roll out the pie dough to a 12-inch round. Leaving a one inch border, top with gruyere cheese. Add mushrooms and shallots. Salt and pepper to taste, then fold the uncovered dough over the mushrooms in an overlapping fashion, leaving some of the center exposed. The nice thing about galettes is that it doesn’t have to be perfect!
Brush the exposed dough liberally with egg. Sprinkle with flaked sea salt for finishing.
Cover the exposed mushrooms only with tinfoil and bake at 400 degrees Fahrenheit for 20 minutes. Remove tinfoil and bake for another 15-20 minutes, until crust is golden. Slice and serve warm.