Make the crust: Combine flour, sugar, and salt in a food processor and pulse to blend. Add butter, pulsing, until mixture resembles small peas. Add ice water and continue to pulse until mixture just begins to come together in moist clumps; if mixture is too dry add a bit more water a tablespoon at a time. Gather dough into a ball, flatten into a disc, wrap in plastic and chill for at least 1 hour or freeze for up to a month.
Make the filling: In a large bowl toss together sliced apples, brown sugar, cornstarch, cinnamon, zest and vanilla. Set aside.
Make the crumble: In a medium bowl, mix together granulated sugar, flour, brown sugar, and cinnamon. Drizzle in melted butter and, using a fork, stir until mixture is crumbly and all the flour is incorporated; the crumbs should be smaller than 1 inch. Add chopped pecans if desired.
Heat oven to 375 degrees and line a baking sheet with parchment paper. Remove dough from refrigerator and let sit at room temperature for 10 to 15 minutes. On a lightly floured surface, roll the dough into a 14-inch circle (if you're lucky). Transfer to baking sheet and chill until firm, about 15 minutes.
Remove baking sheet from refrigerator and let soften for 1 to 2 minutes. Arrange apples in the center of the dough, dot with butter, leaving a 3-inch border all around; reserve the juices. Brush exposed dough border with beaten egg and fold edge in up over fruit, making pleats every 2 inches. Pour remaining juices over exposed fruit, brush the folded outer edge with beaten egg or cream, and sprinkle with raw sugar. Cover exposed fruit with about 1 cup crumble.
Bake crostata until crust is golden brown and filling is bubbling, about 40 to 50 minutes. Remove and let cool before serving. Serve with Bacon Toffee Sauce