Ingredients

Cookie Chunks

• ½ cup butter, softened
• ½ cup brown sugar, tightly packed
• ¼ cup granulated sugar
• 1 large egg
• ½ teaspoon pure vanilla extract
• ¾ cup all-purpose flour
• ½ teaspoon baking soda
• ¾ teaspoon cinnamon
• ⅛ teaspoon nutmeg
• ¼ teaspoon salt
• 1 ½ cup old fashioned oats

Ice Cream

• 2 cups whole milk
• ½ cup granulated sugar
• ½ cup pure maple syrup
• 2 teaspoons ground cinnamon
• 2 cups heavy cream
• 1 teaspoon pure vanilla extract
• 1 teaspoon coarse kosher salt

Instructions

Make the Oatmeal Cookie Chunks

• To make the cookie chunks, preheat the oven to 350ºF. Line a baking sheet with a Silpat or parchment paper. and set aside.
• In the bowl of a stand mixer fitted with the paddle attachment, combine butter, brown sugar, and granulated sugar on medium speed until light and fluffy. Add the egg and vanilla and mix again until fully incorporated. Add the flour, baking soda, cinnamon, nutmeg, and salt and mix until just combined. Add the oats and pulse until just combined again.
• Spread the cookie dough in an even layer about ½ inch thick on the prepared baking sheet. Bake 11-13 minutes or until just starting to brown on the edges and set in the middle. Let cool completely on the baking sheet. Break the cookie into bite sized chunks and transfer to a freezer safe container. Freeze until ready to incorporate into the ice cream base.

Make the Ice Cream

• To make the ice cream base, prepare an ice water bath and set aside.

• In a medium saucepan over medium heat, combine milk, sugar, maple syrup, and cinnamon. Cook, stirring occasionally, until the mixture just begins to foam around the edges and the sugar has dissolved, about ten minutes (do not boil). Add the cream, vanilla, and salt and stir to combine. 
• Prop open a gallon size plastic freezer bag (I like to set it in a 4 cup glass measuring cup for stability). Pour the ice cream mixture into the freezer bag, remove most of the air, and seal.
• Settle the freezer bag in the ice water bath and allow to rest, massaging the bag once or twice, until cooled, about 30 minutes. Transfer the plastic freezer bag to the refrigerator (I return it to the glass measuring cup) and chill 1 hour or up to overnight.（You can also directly select the cooling - only mode of the ice cream maker for chilling.）
• Lightly stir the chilled mixture, transfer it to an ice cream maker, and process it in ice cream mode. Add the frozen cookie chunks during the last two minutes of churning, or gently fold them in with a spatula. Transfer the ice cream to an airtight container and freeze for at least 1 hour or up to four days.