Preheat oven to 350°F. Line 2 baking sheets with parchment paper and set aside.
In a mixing bowl, whisk together the flour, oats, cinnamon, baking soda, baking powder, and salt.
2 cups all purpose flour, spooned and leveled, 1/2 cup quick oats, 2 tsp. ground cinnamon, 1 tsp. baking soda, 1/2 tsp. baking powder, 1/2 tsp. kosher salt
In the bowl of a stand mixer fitted with the paddle attachment, add the butter and sugars.
8 Tbsp. unsalted butter, 3/4 cup brown sugar, packed, 1/2 cup white sugar
Beat for ~2 minutes, scraping down the sides of the bowl as necessary. It will look somewhat like a paste.
Add the eggs and vanilla, and mix again until incorporated.
1 large egg, 1 large egg yolk, 1 Tbsp. vanilla extract
Gradually add in the dry ingredients, being careful not to over mix.
Add the carrots.
1 cup grated carrots
Mix with a rubber spatula just until combined.
Using a 2 Tbsp. cookie scoop, scoop the dough and place on prepared baking sheet. I like to bake 6 cookies at a time so you're not over crowding the pan which can lead to your cookies spreading.
Bake for 10-13 minutes or until lightly browned around the edges. They will look very soft, it's OK, they set up as they cool. Allow the cookies to rest on the baking sheet for about 5-10 minutes, then transfer to a wire rack to cool completely.
Place the cookies in the freezer for just 15-20 minutes so they are easy to work with when assembling the sandwiches. If the cookies are warm or super soft, it can be hard to work with.
Assemble the cookie sandwiches: scoop about 1/2 cup of ice cream onto the bottom of one cookie, then sandwich another cookie on top of it. Gently press the cookies together so the ice cream is even along the edges of the cookies.
1 gallon vanilla bean ice cream
Tightly wrap each cookie sandwich individually in plastic wrap and freeze until the ice cream is firm, at least 2-3 hours or ideally up to overnight. If you enjoy the cookies right away without freezing, the ice cream will squeeze out the sides and it becomes very messy.
You can enjoy the ice cream sandwiches straight from the freezer, or I like to wait just a few minutes before I take my first bite!