• Preheat the oven to 425℉.

For the filling

• Peel and core the apples. Cut them into slices. Mix apples with lemon juice, sugar and cinnamon.
  10 large apples, 1 cup sugar, 3 Tbsp lemon juice, ½ tsp ground cinnamon
  
• Heat the big skillet with butter. Add the apple mixture into a skillet. Cook for about 15 minutes on low medium heat, stirring a few times. Apples should soften, but still hold it’s shape.
  2 Tbsp butter
  
• Add cornstarch, stir well, cook for a couple of minutes more and set aside. The filling should be completely cold before assembling the pie.
  3 Tbsp cornstarch
  

For the crust

• Mix flour, salt, and sugar. Add cold butter.
  2½ cups gluten-free flour blend, 2 Tbsp sugar, ¼ tsp salt, 1 cup butter,
  
• Use a knife or hands to make small clumps.
  
• Add cold milk. Begin with 5 tbsp, but maybe you will need 1-2 more. Mix until the dough starts coming together. This can also be done in a food processor.
  7 Tbsp cold milk
• Make 2 equal balls, flatten them into discs, wrap each of them with plastic wrap, and place them in the fridge for about an hour.
  
• Take the first disc from the fridge. Sprinkle the working surface and rolling pin with flour and roll the dough out into a 12-inch diameter circle.
  
• Using a rolling pin, place the dough into a pie dish.
  

Assemble:

• Place the apple filling into the crust.
  
• Take the second disc out of the fridge, and roll it out to a 12-inch circle. Use a large knife or pastry wheel to cut ten wide strips from the rolled dough.
  
• Put strips over filling, forming a lattice. Fold and seal the edges. Place the pie into the fridge for 30 minutes. If you want, you can brush the pie with egg & milk mixture.*
  
• Bake the pie in the preheated oven at 425°F for 15 minutes, then cover the edges with a foil, reduce the heat to 350℉ and bake for 40 minutes.
  
• Take it out of the oven, and let it completely cool. Serve with a big scoop of ice cream.