Preheat the oven to 175ºF. Using an apple corer or a sharp knife, remove the cores of the apples. Thinly slice the apples 1/8-inch thick horizontally. (Use a mandoline for even slices. This ensures even cooking as well.)

Place the apple slices in a bowl and add the lemon juice and vanilla. Toss to coat evenly. Add the remaining ingredients and toss again. Place the apples on wire racks on baking sheets and bake for 4-6 hours until totally crispy. (If you have a dehydrator, place the apples on racks and dehydrate at 175ºF for 4-6 hours.) Store in an airtight container.