*When using a gluten-free flour substitute, I have had better results when using the weight of all-purpose flour as opposed to the often-heavier GF variety. (For instance, Bob’s Red Mill’s Gluten Free 1-to-1 Baking Flour weighs 20 grams more per cup than standard all-purpose flour, and I think this difference can create a heavier outcome in GF baked goods.)
Option: Those who enjoy the addition of chocolate chips, chunks, or nuts may add ½ to 1 cup to the batter. In my last batch, I sprinkled a scant ½ cup of chocolate chunks over the top before baking. For a salty-sweet touch, I have also reduced the salt in the batter to ¼ teaspoon and then sprinkled ¼ teaspoon flaky sea salt over the surface before baking.
Storing: The brownies may be stored in an airtight container at room temperature, although refrigeration will prolong freshness. Tightly wrapped, the brownies will keep for a week or more in the refrigerator and freeze well, too.