Pre-heat the oven to 325°F Line the bottom of a greased and
floured 8 x 8 square baking pan with parchment paper.
In the top of a double boiler, melt together butter and
chocolate chips over medium heat, stirring often, until
smooth. Remove from heat and let cool for 5 minutes.
Whisk in sugar and vanilla until well combined. Whisk in eggs,
one at a time.
In another bowl stir together the almond flour, brown rice
flour, and salt. Add this to the chocolate mixture and beat well
with a wooden spoon for 1 minute.
Transfer the batter to the prepared pan and spread to the
edges. Bake until top is crackled and a toothpick inserted
near the center comes out cleanly, 20 to 25 minutes. Cool
completely before removing from pan on parchment and
cutting into squares.