Here is my recipe - you can tweak it to your tastes as you like.
6 apples, peeled, cored, and cut into chunks (I used 4 granny smith and 2 red delicious because that's what I had, but you can use whatever you like to eat)
1 1/2 cups water
Juice and zest of 1 lemon
1/4 cup sugar (depending on your taste/sweetness of your apples you may need more/less)
Directions: Place all ingredients into a large saucepan or dutch oven over medium heat. Cook covered for 20-30 minutes, or until apples get nice and soft. Remove from heat and cool; mash with a potato masher or fork.
You could put it in the food processor or mill if you want it to be smoother but I like a few chunks in mine. Also, cinnamon would be a logical addition but I ran out.