In a small bowl combine flour, cocoa powder baking powder and salt

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Separate egg yolks and egg whites into separate large bowls. Whites in one bowl, yolks in the other. Beat whites until foamy, gradually add 1/4 cup sugar and beat until stiff peaks.

Beat egg yolks with remaining 1/2 cup sugar and vanilla until thick and light, 2 to 3 minutes.fold in flour/chocolate mixture just until combined

Fold 1/4 of egg white mixture into yolk mixture then fold in remaining whites

Spread batter evenly in prepared pan. Bake 12 to 13 minutes until.toothpick comes out clean

Cool 2 minutes on wire rack, meanwhile dust clean dry kitchen towel with confectioners sugar. Run a small sharp knives around edges of cake to release any stuck pieces. Invert cake on prepared kitchen towel and carefully peel of parchment paper

Roll cake up in towel.using towel to roll.in long cylinder, cool on rack while preparing ice cream

Have ice cream.softened enough to be able to spread. Unroll.cake and spread ice cream.evenly over cake

Roll cake up tightly using towel to just help. Don't worry about cracks they will be covered with frosting later Wrap. well in parchment paper and foil and frezze overnight

Place chopped chocolate in a large bowl. Heat cream just until hot in microwave or stovetop, pour over chocolate let sit 1 minute then stir until smooth

Chill mixture until cold at least 2 hours. When ready to frost cake beat. chocolate until creamy

Slice and serve with Coffee Cream Anglaise and Hot Fudge Sauce recipes attached below

https://cookpad.wasmer.app/us/recipes/359845-hot-fudge-sauce
https://cookpad.wasmer.app/us/recipes/339891-coffee-creme-anglaise