1. Preheat the oven to 350°F. Line an 8-inch square baking pan (see note) with two pieces of foil long enough to overlap on all four sides. Lightly oil the foil.
2. Put the almond flour, brown rice flour, cocoa powder, cinnamon, baking soda, and salt in a bowl and stir with a whisk to combine.
3. Put half of the chocolate in a heatproof bowl and set the bowl over a saucepan of simmering water. Heat, stirring often, just until the chocolate is melted and smooth. Remove from the heat and whisk in the olive oil.
4. Crack the eggs into a large bowl and whisk until frothy. Slowly add the maple syrup and maple sugar, whisking all the while, and continue whisking until the mixture is smooth. Add the vanilla extract, then gradually add the chocolate, whisking vigorously all the while, and continue whisking until smooth and glossy.
5. Add the flour mixture and beat for about 1 minute. Stir in the remaining chocolate and the walnuts. Scrape the mixture into the prepared pan and smooth the top with a spatula.
6. Bake for 30 minutes or until a toothpick inserted in the center comes out clean.
7. Let cool to room temperature in the pan, then cover and refrigerate for at least one hour before cutting into 16 brownies.
Variation: For brownies that are more fudgy, replace the rice flour with another 1/3 cup of almond flour.
Cook's Note: You can also use a 9 by 6-inch baking pan. If you do, the baking time will be only about 25 minutes.
Prep Time: 20 minutes
Cook Time: 30 minutes
Storage: Store in an airtight container in the refrigerator for up to 5 days or in the freezer for up to 3 months.
Go to full version of