Preheat oven to 350°F (175°C). Grease an 8-inch springform pan, line the bottom with parchment paper, and dust the sides with cocoa powder.
Melt the chopped dark chocolate and butter together in a double boiler over gently simmering water until smooth and glossy. Remove from heat and cool slightly.
In a separate bowl, whisk the room temperature eggs and sugar vigorously for 3-4 minutes until pale, thick, and doubled in volume.
Slowly pour the cooled chocolate mixture into the whipped eggs, whisking gently. Stir in the premium vanilla extract.
Sift the almond flour, cocoa powder, and sea salt over the wet ingredients. Fold gently with a spatula using a 'J' motion until just combined. Do not overmix.
Pour batter into the prepared pan and smooth the top. Bake for 25-30 minutes until the edges are set but the center still jiggles slightly to ensure the best gluten free chocolate cake texture.
Cool completely in the pan on a wire rack before removing the springform ring. Dust with extra cocoa powder before serving.
