Mark Best: Chocolate chantilly with raspberry-poached rhubarb

1.Combine chocolate and 230ml water in a heatproof bowl over a saucepan of simmering water, stirring occasionally until melted and well combined (3-4 minutes). Place bowl over a bowl of iced water and whisk steadily until chocolate thickens and increases in volume (4-5 minutes). Refrigerate, covered, until required.

2.Meanwhile, for raspberry-poached rhubarb, trim leaves and white ends from rhubarb (discard). Wash well, dry, then peel each stalk with a vegetable peeler. Place peelings in a large heatproof bowl with raspberries and sugar (reserve stalks). Cover bowl tightly with plastic wrap and place over a saucepan of simmering water until a red juice forms (40-45 minutes).

3.Strain juice through a fine sieve into a 2 litre-capacity wide saucepan. Do not press solids through (discard solids). Cut reserved rhubarb into 9cm lengths, add to pan and simmer over low heat until just tender (6-8 minutes). Do not boil. Transfer rhubarb and juice to a container and refrigerate until chilled (30-40 minutes). Before serving, gently toss with raspberries to combine.

4.Form six quenelles of chocolate with a large, hot spoon and place each in a serving bowl. Divide a little rhubarb and raspberry mixture among bowls, drizzle with rhubarb juice to taste and serve with extra rhubarb and raspberries to the side.