01 -
Using powdered gelatin: In a small dish, mix 7.7g of plain gelatin with 40g of ice-cold water, making sure it’s evenly moistened. Chill in the fridge for roughly 10 minutes until solid. For gelatin sheets: Fully soak 4.5 sheets in a bowl of icy water for about 10 minutes until they’re flexible and soft.
02 -
Process fresh raspberries until velvety smooth using a blender or food processor. Strain the mixture through a fine sieve to get 270g of seed-free puree for the mousse. If you also want to make the sauce, save another 170g of strained puree for later.
03 -
Warm 90g of raspberry puree (about a third of the total) until it’s heated through but doesn’t boil (122-140°F/50-60°C). Stir the gelatin into the warm puree until it’s fully dissolved. Combine this mix with the rest of the puree, then stir in the 15g of lemon juice. Leave it to cool at room temp.
04 -
Chill a big mixing bowl and whip up 320g of heavy cream until firm peaks show. The cream should feel soft but sturdy. Store in the fridge until ready to use.
05 -
Add 90g of egg whites to a grease-free bowl and whisk until they foam. Slowly sprinkle in 13g of sugar, one bit at a time, continuing until soft peaks form. Separately, heat 130g sugar and 60g water in a small pot to 244-246°F (118-119°C). Brush the pan’s sides with water to stop crystals from forming. Drizzle this piping-hot syrup into the egg whites while beating, and continue until glossy meringue forms and the bowl feels neutral (not warm or cold).
06 -
Carefully mix the meringue into the whipped cream, stopping halfway through. Add half the raspberry and gelatin mixture, folding it gently, then the other half. Finish folding delicately with a spatula, scraping the sides and bottom to avoid clumps. Be gentle to keep the mousse light and fluffy.
07 -
Spoon or pipe the mousse into dessert glasses straight away. Let it chill for 3-4 hours in the fridge until solid. To make the optional raspberry sauce, combine 170g raspberry puree with 17g sugar and 5g lemon juice in a pot. Bring it to a boil, cool in the fridge, and use it to drizzle over the mousse before serving.