Preheat oven to 350. Line a cookie sheet with parchment paper.
Combine the first four ingredients in a large bowl and mix with an electric mixer until smooth. Add the rest of the ingredients for the cookies and mix just until well combined. Scoop 18 large cookies. Bake for 15-20 minutes until firm to the touch when lightly pressed.
Beat the filling ingredients until smooth. Spread or pipe on the bottom of one cookie and top with a second cookie to sandwich the filling.
Notes
Nutrition: this recipe makes 9 very large sandwich cookies. Each cookie has 5 NET carbs and 12 grams of protein. One cookie is a great meal replacement. You may make them half the size shown for a small carb count per cookie to have a snack or dessert.Prep Time: prepare the cookie dough batter up to 1 day ahead of time and refrigerate until you are ready to bake them. To Store: wrap the cookies in plastic wrap and put them inside of a food storage container. This gives an added layer of protection, and they will last up to 4 days in the fridge.To Freeze: keep the cookies wrapped up and freeze for up to 2 months. They should be stored airtight and thawed in the fridge when ready to serve. Notes on Sweeteners: