Preheat oven to 350 degrees. Butter two 9-inch springform pans. Line the bottoms with parchment paper, and butter the paper; set aside. Place chocolate and butter in a heatproof bowl, and set over a pan of barely simmering water. Stir occasionally until melted; set aside.
Sift together flour and salt; set aside. Place sugar and eggs in the bowl of an electric mixer fitted with the paddle attachment, and beat until fluffy and well combined, 3 to 5 minutes. Add vanilla and chocolate mixture, and stir to combine. Add dry ingredients, and stir to combine. Divide batter between the two pans using an offset spatula to distribute batter evenly, and smooth the layers. Bake until the center is set, about 20 minutes. Transfer pans to a wire rack to cool completely before unmolding.
Place one layer on a 9-inch cardboard cake round. Spread filling over the layer, and invert the second layer onto the top, leaving the smooth side up. Press down gently on top layer to evenly distribute filling to edges. Using a metal spatula, smooth filling flush with sides of cake. Refrigerate until ready to glaze.
Carefully transfer torte off cardboard round onto a wire rack set over a baking pan. Pour enough ganache glaze over cake to fully coat, shaking pan gently to help spread ganache if necessary. Let sit for 15 to 20 minutes. The ganache in the pan may be melted and strained through a fine sieve and added back to glaze. Pour remaining glaze over torte, allowing excess to drip off sides. If top is not smooth, gently shake pan or run an offset spatula quickly over surface. Allow to set at least 30 minutes before serving. Carefully slide the cake off of the wire rack and onto serving platter.