Tiramisu Yule Log

INGREDIENTS

• Confectioners' sugar for dusting
• 1/2 stick (1/4 cup) unsalted butter, melted and cooled
• 3/4 cup heavy cream
• 1/4 teaspoon ground cinnamon
• Unsweetened cocoa for dusting
• 1 teaspoon vanilla
• 1/2 cup espresso or very strong black coffee
• 2 tablespoons light corn syrup
• 1/4 teaspoon salt
• 8 ounces mascarpone cheese
• 1/2 cup sifted cake flour (not self-rising; sift before measuring), plus additional for dusting pan
• 5 large eggs, separated, left at room temperature for 30 minutes
• 12 ounces 60% bittersweet chocolate, finely chopped
• 1/2 cup plus 2 tablespoons granulated sugar, divided
• 1/2 cup chilled heavy cream
• 2 tablespoons sugar
• 2 tablespoons confectioners' sugar
• 1/4 teaspoon cream of tartar
• 1/4 cup granulated sugar
• 1 tablespoon Cognac or brandy