Guy Savoy's Spinach and Mushroom Gratin

The reduction of the cream makes this gratin very special. From "Guy Savoy: Simple French Recipes for the Home Cook."

• Ready In: 40 mins
• Serves: 4

Ingredients

• 1  lb white mushroom
• 1 1⁄2 tablespoons unsalted butter, plus more for buttering the dish
•  salt
• 1  lb spinach, stemmed, washed and drained (about 2 bunches)
• 1 1⁄4 cups heavy cream
•  fresh ground black pepper
•  sea salt

Directions

1. Clean the mushrooms and cut them into one-eighth-inch slices.
2. In a medium skillet, heat the butter over high heat just until melted, then add the mushrooms and sauté them until golden, about 10 minutes. Drain any liquid from the mushrooms and set them aside.
3. Place 2 quarts of water in a medium stock pot with one-half teaspoons salt.
4. Bring the water to a boil over high heat, then stir in the spinach and blanch for just a few seconds, until wilted and bright green in color.
5. Remove the spinach using a slotted spoon to a large bowl of ice water until cool. Drain the spinach well, squeezing out any excess water.
6. Heat the oven to 350 degrees F.
7. Reduce the cream to one-half cup in a small saucepan over low heat.
8. Strain the cream into a small bowl and season with a pinch each of salt and pepper.
9. Butter a small (2-quart) baking dish, and spread the spinach in the bottom in an even layer.
10. Sprinkle the top of the spinach with one-eighth teaspoons salt.
11. Arrange the mushroom slices over the spinach in a fish-scale pattern.
12. Spoon the cream evenly over the top and bake for 5 to 10 minutes, until heated through. Serve immediately.