Chocolate Fudge Cake: Grease 8-inch (2 L) springform pan; line bottom and side with parchment paper. Set aside. In small saucepan, melt chocolate with butter over medium-low heat until smooth, about 5 minutes. Let cool slightly. In large bowl, beat together eggs, sugar and salt until pale and thickened, about 5 minutes. Stir in chocolate mixture, flour, rum and vanilla until combined. Scrape into prepared pan, smoothing top.