Vegan Mousse au Chocolat with Aquafaba

Pour the reserved aquafaba into a small saucepan. Finely chop the chocolate. Open the chilled coconut cream and scoop out only the solid cream into a large mixing bowl, discarding any watery liquid. Measure out the sugar, cream of tartar, vanilla, and salt.

Simmer the aquafaba over medium heat, stirring occasionally, until reduced to approximately 100ml — about 8-10 minutes. Transfer to the fridge and cool completely until cold to the touch, at least 20 minutes.

Place the chopped chocolate in a heatproof bowl set over a saucepan of barely simmering water, ensuring the bowl does not touch the water. Stir gently until fully melted and smooth, then remove from the heat and stir in the vanilla, salt, and cognac if using. Allow to cool to room temperature — the chocolate should feel just warm, not hot, to the touch.

Whip the chilled coconut cream with a hand mixer on high speed until it forms soft, billowy peaks — about 2 minutes. Set aside.

Using a clean, dry bowl and beaters, whip the cooled aquafaba with the cream of tartar on medium speed for 2 minutes until foamy, then increase to high and add the caster sugar one teaspoon at a time, whipping until the mixture holds glossy, stiff peaks — about 6-8 minutes total.

Fold the whipped coconut cream into the cooled melted chocolate using a large spatula until fully combined.

Add one-third of the aquafaba meringue to the chocolate mixture and stir firmly to loosen the base — do not worry about deflating this portion.

Add the remaining meringue in two additions, folding gently with wide, deliberate strokes from the bottom of the bowl upward, rotating the bowl each time, until no white streaks remain and the mixture is uniformly airy.

Divide the mousse between four serving glasses or ramekins, smoothing the tops lightly. Cover each with cling film and refrigerate for a minimum of 4 hours, or overnight, until fully set and cold throughout.

Remove from the fridge 10 minutes before serving. Dust with cocoa powder or scatter dark chocolate shavings over the top, and serve immediately.