1. Preheat oven to 350°F. Mist a 12-cup muffin tin and 4 cups of a 6-cup tin with gluten-free cooking spray.
2. In a bowl, whisk rice flour, almond meal, baking soda, salt and cinnamon. Place chocolate and butter in a heatproof bowl; set over a pan of simmering water. Let stand until chocolate and butter have melted, stirring often. Remove from heat; whisk in cocoa.
3. In a large bowl, using an electric mixer, beat eggs and sugar on medium speed until smooth. Beat in vanilla. Slowly add chocolate mixture; beat on low for 1 minute. Beat in flour mixture.
4. Fill each muffin cup 2/3 full. Bake until a toothpick stuck into middle of a brownie comes out clean, about 15 minutes. Let cool in pans on a wire rack for 5 minutes, then remove to rack to cool completely.
Note: Nutritional analysis is per brownie.