In a medium bowl, whisk together the flour, sugar, and salt. Using a pastry cutter or 2 forks, cut in the butter until the mixture resembles coarse pea-sized crumbs. Add the water and stir until the flour is moistened. Add 1–2 more Tablespoons of water if the dough seems dry. Turn the dough out onto a lightly floured work surface and, using your hands, work the dough into a ball. Flatten it into a thick disc. Wrap the dough disc in plastic wrap or parchment paper and refrigerate it for at least 2 hours, and up to 3 days.

In a medium bowl, combine the brown sugar, cinnamon, flour, and walnuts. Using a silicone spatula, stir in the melted butter. The topping will be thick and crumbly. Place it in the refrigerator while you continue.

On a floured work surface, roll out the disc of chilled dough. Turn the dough about a quarter turn after every few rolls until you have a circle 12 inches in diameter. Carefully place the dough into a 9-inch pie dish. Tuck it in with your fingers, making sure it is smooth. Use a small paring knife to trim excess dough off the edges. Flute the pie crust edges and brush them with egg wash. Place the pie crust in the refrigerator.

In a large bowl using a silicone spatula or wooden spoon, combine the apples, sugar, flour, lemon juice, cinnamon, cloves, nutmeg, and vanilla extract, stirring until the apples are all coated.

Preheat the oven to 400°F (204°C). Place a baking sheet on the bottom oven rack to catch any juices that may bubble over.

Spoon the apple filling into the crust, making sure there are no large gaps between the slices. It’s a lot of filling! Sprinkle the cold crumb topping evenly over the top of the apples.

Bake for 20 minutes. Add a pie crust shield to prevent the edges from browning too quickly, and reduce the oven temperature to 375°F (191°C). Bake for an additional 35 to 45 minutes or until the crust is golden brown and juices are bubbling around the edges. If needed toward the end of bake time, remove the pie crust shield and tent a large piece of aluminum foil over the entire pie if the crumb topping is getting too brown.

Allow the pie to cool for at least 3 full hours at room temperature before serving. This time allows the filling to thicken up. Serve with vanilla ice cream and salted caramel sauce, if desired. Cover leftover pie and store in the refrigerator for up to 5 days.