Preheat the oven to 325 degrees F.

Butter the bottom and sides of a 9-inch springform pan and line the bottom with parchment paper.

Place the 2 chocolates in the top of a double boiler and stir until melted over low heat.

Put eggs, brown sugar and salt in mixer bowl.

Place mixer bowl over the water from the double boiler and whisk to warm eggs, 2 mins.

Transfer the bowl to the stand mixer and beat on medium 5 mins.

On low, add the coffee/vanilla, then the melted chocolate.

Once mixed add the butter slowly to incorporate.

Pour into pan and bake 30-35 mins until toothpick comes out with few crumbs.

Cool, run knife around edge and remove ring.

Microwave the chocolate, butter and corn syrup until melted.

Whisk the sugar, egg whites, cream of tartar, salt and 1/3 cup water in the top of a double boiler over simmering water.

With a handheld mixer, beat on low then slowly increase to high to reach soft s-about 5mins.

Remove from heat and continue beating until more stiff for nice peaks a few mins.

Spread on cooled cake and "pull" peaks with a fork. Drizzle with the melted chocolate mix.