Every apple pie recipe is great, and the best tasting apple pie is the one that you didn't have to make but get to eat. But, here's a recipe to how bakery "professionals" approach an apple pie, if you're curious. It's the method that is taught in some pastry classes.
Peel, core and slice the apples. Place in a bowl, and stir in 1/2 of the sugar (1/2 cup) until they are all coated. Dump into a colander, and let the colander "bleed" juice back into this bowl that you just emptied the apples out of.
Meanwhile, make your top and bottom pie crusts.
Start heating oven to 180 C / 350 F / Gas Mark 4.
Drain the juice that bleeds off the apples into a small saucepan, add cinnamon and salt to taste, bring to a boil. Dissolve the corn starch in the cold water, add to the juice, and bring back to the boil, then remove from heat. Add the remaining 1/2 cup of sugar to the juice and stir well. Then stir in the butter.
Put the bottom crust in the pie tin. Arrange the apples. Pour the juice syrup over the apples, cover with top crust and bake for about 35 minutes or until done.
Good pie apples to use (in North America) are Northern Spy, Wealthy and Rome Beauty. In the UK, Bramley will do quite nicely.You only use half the sugar to bleed the apples, as using all of it would make a juice too sweet to thicken properly.In apples, much of the pectin, a natural thickening agent, is concentrated just under the skin. So when you peel them, make an effect to remove just the peel and as little of the flesh under the apple as possible.See the entry on "Pie Tips" for giving it a professional look.