Ingredients
3/4 cup all-purpose flour3/4 cup whole wheat flour1 teaspoon kosher salt10 tablespoons cold unsalted butter1 to 3 tablespoons ice waterFILLING:2 tablespoons unsalted butter, divided2 medium leeks (white portion only), cut into 1/4-inch slices2 teaspoons kosher salt, divided1 tablespoon olive oil1/2 pound sliced baby portobello mushrooms1 pound fresh asparagus, trimmed and cut into 3-inch pieces1 log (4 ounces) fresh goat cheese1 large egg, lightly beaten
Preparation
Place flours and salt in a food processor; pulse until blended. Add butter; pulse until butter is the size of peas. While pulsing, add just enough ice water to form moist crumbs. Shape dough into a disk. Cover and refrigerate 1 hour or overnight.
In a large skillet, heat 1 tablespoon butter over medium heat. Add leeks and 1 teaspoon salt; cook and stir until softened, 5-7 minutes. Reduce heat to medium-low; cook until deep golden brown, 25-30 minutes, stirring occasionally. Remove from pan to a large bowl.
In the same skillet, heat oil and remaining 1 tablespoon butter over medium heat. Add mushrooms and remaining 1 teaspoon salt; cook and stir until reduced by half and crispy, about 20 minutes. Add to bowl with leeks.
Meanwhile, in a Dutch oven, bring 8 cups water to a boil. Add asparagus; cook, uncovered, until the stalks turn bright green, 2-3 minutes. Remove asparagus and immediately drop into ice water. Drain and pat dry; add to bowl with leeks and mushrooms.
Preheat oven to 400°. On a lightly floured surface, roll dough into a 12-in. circle. Transfer crust to a parchment-lined baking sheet.
Crumble goat cheese over top of vegetable mixture. Spoon over crust to within 2 in. of edge. Fold crust edge over filling, pleating as you go and leaving a 6-in. opening in the center. Brush folded crust with beaten egg. Bake until crust is golden brown and cheese is melted, 30-35 minutes. Let stand 5 minutes before cutting. Serve warm or at room temperature.
