• Preheat the oven to 350°F. Line two baking sheets with parchment paper and set aside.

Make the Cookies:

• In the bowl of a stand mixer, cream together the butter, brown sugar, and granulated sugar until light and fluffy.
  1 cup butter, ¾ cup dark brown sugar, ½ cup granulated sugar
• Add eggs, honey, and vanilla and beat until incorporated.
  2 eggs, 1 tablespoon honey, 1 teaspoon vanilla extract
• In a separate medium sized bowl whisk together flour, baking soda, cinnamon, and salt. Slowly add the flour mixture into the butter mixture and mix just until incorporated.
  1¾ cup all purpose flour, 1 teaspoon baking soda, ½ teaspoon salt, ⅛ teaspoon cinnamon
• Stir in the oats until evenly mixed. Transfer dough to a large mixing bowl (you will need the stand mixer bowl to make the filling). Chill the dough in the refrigerator for 15 minutes.
  1½ cups quick cooking oats
• Remove the dough from the refrigerator and drop by tablespoons onto baking sheet. Bake for 8 to 10 minutes, just until the edges start to brown. The cookies will seem moist in the middle, but they will set up.
• Cool on the cookies on the baking sheet until they are set, and then transfer the cookies to a wire rack to cool completely.

Make the Filling:

• In the top of a double boiler (or a heatproof bowl set on top of a pan of simmering water), add the egg whites, sugar and cream of tartar.
  2 egg whites, ½ cup granulated sugar, ¼ teaspoon cream of tartar
• Whisking frequently, heat the mixture until it becomes very frothy and the sugar is dissolved, approximately 160°F.
• Carefully add the egg mixture to the bowl of a stand mixer fitted with the whisk attachment. Whisk on high speed for several minutes until stiff peaks form and the mixture is light in texture.
• Carefully fold in the vanilla.
  ½ teaspoon vanilla extract

Assemble the Pies:

• Pair up the cookies by size so the cookies that will be sandwiched together are closest in size. Place one cookie bottom side down and one bottom side up.
• Transfer the filling to piping bag fitted with a large round tip or to a resealable gallon sized bag with a corner snipped off. Pipe a dollop of filling in the center of each cookie with the bottom facing up.
  
• Place the matching cookie on top of the filling to create a sandwich. Repeat with remaining cookie pairs.
  
• Store the cookie pies in an airtight container.