Prepare the Peaches. Start by peeling the peaches. You can do this by blanching them in boiling water for about 30 seconds and then immediately transferring them to an ice bath. The skins should easily peel off. Once peeled, slice the peaches into wedges or desired shape.
Combine the Ingredients. In a mixing bowl, combine the peach slices, lemon juice, vanilla extract, and ground cinnamon. Gently toss the peaches to coat them evenly with the lemon juice and spices. Let the mixture sit for about 10 minutes to allow the flavors to meld.
Thicken the Filling. In a small bowl, whisk together the cornstarch or arrowroot powder and unsweetened apple juice or water until smooth. This mixture will act as a natural thickener for the peach filling.
Cook the Filling. Transfer the peach mixture to a saucepan and heat it over medium heat. Once the peaches start to release their juices, add the cornstarch mixture to the saucepan. Stir continuously to prevent any lumps from forming.
Simmer and Thicken. Reduce the heat to low and allow the peach mixture to simmer gently. Stir occasionally until the filling thickens and coats the back of a spoon. This process usually takes about 5-7 minutes. Keep a close eye on it to prevent scorching.
Serve and Enjoy! Serve your no sugar added peach pie filling with one of my favorite serving suggestions below and enjoy!