1 1/2 Cups Dark Chocolate (85% or higher), chopped (7 ounces or 200 grams of dark chocolate)
1/2 Cup Unsalted Butter
1/2 Cup Heavy Whipping Cream
4 Eggs, separated
1/2 Cup Truvia blend (Can substitute with other no/low carb sweeteners)
Preheat your oven to 325°F/160°C. Grease an 8-inch cake pan and line with a piece of parchment paper.
In a large, microwave-safe bowl, add the dark chocolate, butter, and heavy cream. Melt together by heat the chocolate mixture in 30-second intervals until the butter and chocolate are completely melted. Whisk together the chocolate mixture until smooth. Add the egg yolks, one at a time, mixing until just incorporated. Add the Truvia blend, and mix well to combine.
In a separate large bowl, whip the egg whites until stiff peaks form. Take 1/3 of the whipped egg whites and whisk into the chocolate mixture, to lighten. Gently fold the remaining egg whites, 1/3 at a time, into the chocolate mixture until no white streaks remain.
Bake for about 45 minutes, until the cake is set but the center jiggles slightly. Allow cake to cool until close to room temperature before serving.
If the chocolate mixture looks like it is separating, continue to whisk it for a few more minutes and it will eventually emulsify into a shiny, smooth ganache. An immersion blender or a hand mixer will quickly re-emulsify the chocolate mixture.
Be careful not to over-beat your egg whites while whipping, as this could cause the cake to collapse during or immediately after baking.
Leftover cake freezes well. Cut the cake into slices and freeze in a freezer bag.