With an electric mixer, beat butter,sugar and lemon zest for about a minute or two. Add the egg, and lemon juice and beat until combined.
In a medium bowl, combine all-purpose flour, spelt flour, baking powder, baking soda and salt. At a low speed, gradually add flour mixture until combined.
Cover the cookie dough with plastic wrap and refrigerate for a minimum of 1 hour.
Pre-heat oven to 350°F.
Using an ice cream scoop as a guide to form the balls, roll each ball into with your hands. Place the cookies 2 inches apart on a prepared baking sheet lined with parchment paper.
Bake for 12-14 minutes or until the edges and bottom are golden in colour. Remove cookies and place on cooling rack to cool.
