Preheat oven to 350°
Prepare 2 baking sheets by lining with parchment paper.
In a medium bowl, whisk together flour, baking soda, salt and lemon zest.
Using a stand-mixer with the paddle attachment, begin creaming the butter and granulated sugar until light and fluffy (approximately 2 - 4 minutes on medium speed). Scrape the bowl as needed.
Add the egg and lemon juice and mix on low speed until incorporated.
Add the flour mixture and mix on low speed until combined.
Create 12 flat discs using the dough. Discs should be approximately 1" in diameter and ⅙ of an inch thick.
Scoop the remaining dough onto the parchment-lined baking sheets using a cookie scooper (2 tablespoon per cookie). Leave approximately 2 inches of space between each cookie.
Using the back of a tablespoon or a dough tamper, make an indentation in each cookie. Remove the filling from the freezer and place a disc in the center of each cookie. Place the 12 discs of cookie dough over the lime filling. Roll each cookie to seal the disc inside.
Optional. Roll the cookies in graham cracker crumbs and place back on cookie sheets.
Bake cookies for 14 - 16 minutes or until the tops are a pale golden color.
Let cookies cool on the baking sheets for 5 to 10 minutes, then transfer them to a wire rack to cool completely.