Winter Squash-and-Shallot Tart

Preheat oven to 400°F. Toss together squash, shallots, oil, nutmeg, 1 teaspoon of the salt, and 1/4 teaspoon of the pepper in a large bowl. Spread mixture in a single layer on a rimmed baking sheet. Bake in preheated oven until vegetables are tender, about 30 minutes. Let coo1 15 minutes.

While vegetables cool, roll pastry sheet into a 16- x 10-inch rectangle on a large piece of parchment paper. Carefully transfer parchment paper with pastry rectangle to a large baking sheet. (If needed, re-stretch pastry rectangle.) Using a paring knife, score a 1-inch border around edges of pastry rectangle; prick area inside border with a fork. Bake at 400°F until light golden, about 12 minutes; remove from oven.

Stir together Gruyère, Fontina, egg yolks, crème fraîche, lemon zest, thyme, vinegar, squash mixture, 3/4 teaspoon of the salt, and remaining 1/2 teaspoon pepper in large bowl. Gently spread mixture inside border of baked pastry rectangle.

Return to oven, and bake at 400°F until cheese is melted and crust is golden brown, about 12 minutes. Toss together arugula, lemon juice, and remaining 1/8 teaspoon salt; sprinkle over top of tart. Cut tart into about 4- x 3 1/2-inch pieces, and serve immediately.