Chocolate Torte with Calvados-Poached Figs

Place a rack in middle of oven; preheat to 375 °F. Butter a 9"-diameter springform pan or cake pan and line with a round of parchment. Butter parchment and sprinkle pan with superfine sugar. Melt chocolate in a heatproof bowl set over a saucepan of simmering water (bowl should not touch water), stirring, until smooth; let cool slightly. Pulse hazelnuts, flour, cocoa powder, salt, and 1/2 cup superfine sugar in a food processor until finely ground; sift through a medium-mesh sieve. Pulse any larger pieces again in food processor, if needed. Using an electric mixer on high speed, beat 1 cup butter and remaining 3/4 cup superfine sugar until light and fluffy, about 4 minutes. Add egg yolks, 1 at a time, beating to blend between additions. Beat in vanilla. Reduce speed to low; mix in melted chocolate. Gradually add dry ingredients, mixing just until combined. Using clean beaters and with mixer on medium-high speed, beat egg whites and cream of tartar in a medium bowl until stiff peaks form. Using a rubber spatula, fold 1/3 of whites into chocolate batter to loosen, then fold remaining whites into batter just until combined. Scrape batter into prepared pan. Bake cake 20 minutes, then reduce oven temperature to 350 °F and bake until a tester inserted into the center comes out clean, 30 –40 minutes longer. Transfer pan to a wire rack; let cake cool 30 minutes before unmolding to cool completely. DO AHEAD: Cake can be baked 2 days ahead. Store tightly wrapped at room temperature.