Preheat your oven to 350ºF. Prepare an 8-by-8-inch baking pan by lining the bottom and sides with parchment paper, leaving a slight overhang on two edges. This ensures easy removal of the brownies later.
In a small bowl, whisk together the almond flour, cocoa powder, and salt until well combined. Set this mixture aside for later use.
Melt the bittersweet chocolate and unsalted butter together. You can do this in a double boiler or by placing a medium-large bowl over gently simmering water. Stir continuously until the mixture is smooth and glossy, then remove it from heat.
Incorporate the sugar into the melted chocolate and butter mixture. Whisk until the sugar is fully dissolved and the mixture has cooled slightly. The texture should be velvety.
Add the eggs, vanilla extract, and almond extract to the chocolate mixture. Whisk gently until just combined, being careful not to overmix.
Sprinkle the flour mixture over the chocolate mixture. Using a large rubber spatula, fold it in carefully. You want to combine both mixtures without overworking the batter to maintain that fudgy texture.
Gently fold in the slivered almonds until evenly distributed throughout the batter.
Pour the batter into the prepared baking pan, smoothing it out with a spatula to ensure even baking.
Bake in the preheated oven for 25 to 30 minutes. The brownies are done when a toothpick inserted into the center comes out clean or with a few moist crumbs.
Allow the brownies to cool completely in the pan on a wire rack. For the fudgiest texture, cover and refrigerate for a few hours or overnight before cutting.
To serve, lift the brownies from the pan using the parchment paper overhang. Use a sharp knife to cut into squares. Enjoy your delicious Triple Almond Brownies!