1. Pre-freeze the ice cream machine as directed by the manufacturer.

For the Ice Cream

1. In a medium-sized saucepan, combine the whole milk and all the remaining ingredients except the heavy cream, and vanilla extract. Heat over medium-low heat, stirring frequently just until the dry ingredients are dissolved. Do not allow the mixture to boil.
2. Remove from the heat and transfer to a heat-proof bowl. Stir in the heavy whipping cream and vanilla, mixing to combine. Cover the top of the mixture with plastic wrap and refrigerate for a minimum of 2-3 hours until the mixture is completely rechilled.
3. Prepare the peach filling. Peel and dice the peaches, the smaller the better for quicker cooking. Toss with brown sugar and cinnamon. Cook over medium-low heat for 15-20 minutes, stirring occasionally, add 1 tablespoon of water at a time as needed to prevent sticking. Cook until most of the moisture is evaporated and the peaches are soft. Then mash with a potato masher to create a chunky puree. Cook off any remaining liquid. You should be left with about 3/4 cup of peaches. Chill completely.
4. Churn the ice cream base according to the manufacturer’s instructions, this should take around 20-30 minutes. During the last couple of minutes, add the mashed peaches and walnuts, and reserve a couple of tablespoons to stir in by hand. Transfer the ice cream to a freezer-safe container, layering in the remaining peach filling. Freeze for 4-6 hours before scooping.