Preparation

1. Make the dulce de leche: Put the unopened can of sweetened, condensed co conut milk in the bottom of a large pot and cover with water by at least 2 inches. Place the pot over high heat and bring to a simmer. Cover the pot and reduce the heat to low to maintain a steady simmer for 3 hours. Add water, if necessary, for the can to remain submerged by about 2 inches. Turn heat off and let the can cool to room temperature in the water before removing and opening. This can be made up to a week ahead of time.
2. In a small pot, bring 1 cup of the oat milk to a simmer (this heat will help to activate the xanthan gum). Transfer the hot oat milk to a blender jar, and add the remaining oat milk, corn syrup, salt, vanilla extract, xanthan gum, and cooled dulce de leche. Blend on High until completely smooth and homogenous, 40 to 50 seconds. Cover and refrigerate until well chilled, preferably overnight.
3. Assemble the Mix It In™ Soft Serve Ice Cream Maker with the paddle secured and dispenser handle in its upright position. Turn on and pour in the chilled base. Churn until the desired serving consistency is reached, 25 to 30 minutes. If ice cream is not thick enough, pour back into the freezer bowl and continue mixing until the desired consistency is achieved, checking every few minutes. The ice cream will have a soft, creamy texture.
4. Serve in cups or cones, adding toppings while dispensing ice cream.