In a large bowl, cream butter and coconut sugar. Add in maple syrup and vanilla extract. Beat until the batter is light and fluffy. Add 1 egg and beat until incorporated.
Add in spelt flour, baking soda and kosher salt. The mixture will be slightly sticky. If it’s too much, you can add 1-4 tablespoons of flour.
Pour mixture into a parchment-lined 9×13 baking dish. Bake in a 350° F oven for 10-12 minutes or until the top becomes lightly golden. Set aside.