Step 1: Preheat the Oven - Start by preheating your oven to 350°F (175°C).
Step 2: Prepare the Baking Pan - Line your 8x8 inch baking pan with parchment paper.
Step 3: Cream the Butter and Sugar - In a large mixing bowl, combine the cold unsalted butter and brown sugar. Cream them together until light and fluffy.
Step 4: Add the Egg and Vanilla - Beat in the egg and vanilla extract until well combined.
Step 5: Combine Dry Ingredients - In a separate bowl, whisk together the gluten-free flour, ground cinnamon, baking powder, baking soda, and sea salt.
Step 6: Mix Dry Ingredients into Wet - Gradually add the dry ingredients to the butter mixture and stir until just combined.
Step 7: Fold in the Chocolate Chips - Gently fold in the chocolate chips until evenly distributed.
Step 8: Bake - Spread the batter into the prepared baking pan and bake for 25-30 minutes.
Step 9: Cool and Slice - Allow to cool for about 10 minutes, then lift out and transfer to a wire rack to cool completely before slicing.