Place marrons in the freezer for 2 hours to put them into a stupor; this is the most humane way to cook them. Place marrons in a pan of boiling salted water for 30 seconds. Immediately plunge into cold water until cool. Remove and discard heads, then, using kitchen scissors, cut down the back of the shell. Remove flesh in one piece. Place marrons in a small saucepan, tucking tails under to ensure even cooking, and add onion, thyme, peppercorns, celery and wine. Pour in enough cold water to cover. Cook over medium heat for 4 minutes or until flesh changes colour and is almost cooked through. Remove from heat and cool in liquid. Drain.
To make crisps, fill a deep-fryer or saucepan one-third full with oil and heat over medium heat to 160°C (or until a cube of bread turns golden in 20 seconds). Working in 2 batches, drop potato slices into oil and fry, turning halfway, for 5 minutes or until crisp and golden. Remove with a slotted spoon. Drain on paper towel. Season with salt.
To make the sabayon, place vanilla bean and seeds, egg yolk and Champagne in a heatproof bowl. Place bowl snugly over a pan of simmering water; ensure bowl doesn’t touch the water. Using a tea towel to hold the bowl, whisk vigorously for 8 minutes or until thick and frothy.
Divide cabbage leaves among plates. Place 3 marrons on each leaf and serve with potato crisps and sabayon. Garnish with baby herbs.
Drink 2010 Joseph Drouhin Chablis, Burgundy, France ($37)
Photography by Brett Steven