Vegetable Purées

Ingredients

• For the base (root vegetable — celeriac given as primary example)
• 1 kg celeriac, left whole, unpeeled
• 20 g unsalted butter, cold, cut into small pieces — for drying stage
• For enrichment
• 60 g unsalted butter, cold, cut into small pieces
• 60 ml double cream
• For seasoning
• 1 tsp fine sea salt, plus more to taste; season before enriching
• Optional finish (named in entry)
• 4 drops truffle oil, added off heat only

Method

1. 1
   Steam the whole, unpeeled celeriac over steadily boiling water for approximately 45 minutes. It is done when a skewer meets no resistance at the centre — the flesh yields completely with no raw firmness.
2. 2
   Remove the celeriac from the steamer. Peel it immediately while hot. Spread the peeled flesh on a flat tray and place in a warm oven for 3–5 minutes to drive off surface moisture. The surface should appear dry and slightly mat — no visible steam or wet sheen remaining.
3. 3
   Pass the dried celeriac through a food mill or drum sieve while still hot. Work quickly and completely — the result should be a uniform, lump-free mass. No blender is used at this stage; a food mill or sieve only.
4. 4
   Season the purée now, before any enrichment is added. Fat masks salt perception: the purée correctly seasoned before butter will taste correct after butter; the purée under-seasoned before butter will taste flat regardless of what follows. Taste the plain purée and adjust with fine salt until the celeriac's flavour is clear and present.
5. 5
   THIS IS WHERE THE DISH LIVES OR DIES. Add the cold butter in small pieces, incorporating each piece completely before adding the next — in the manner of monter au beurre. The purée must not be so hot that the butter breaks to grease, nor so cool that it will not emulsify. After the first additions, take a small amount of purée between thumb and forefinger: correctly enriched purée is silken, coating, and slightly warm — no graininess, no visible fat separation, no roughness. If fat separates and feels greasy, the purée was too hot; nothing corrects it, and the enrichment stage must begin again from a correctly tempered base.
6. 6
   Warm the cream separately and add it gradually, tasting between additions. The cream's lactic notes should soften the celeriac's earthiness without eliminating it. Lift a spoonful and allow it to fall: the purée should drop in a slow, cohesive mass — like very thick custard — not run off as liquid nor fall in firm chunks. On the plate it should hold a gentle, rounded mound for 30 seconds before relaxing. If it holds rigidly without relaxing, add a little more cream. If it runs flat at once, return briefly to gentle heat to reduce slightly.
7. 7
   Pass the enriched purée through a fine sieve. Even after the food mill, this final pass produces the refined, service-level smoothness that distinguishes a professional purée. The result should be uniform and silken with no fibrous traces.
8. 8
   Taste a final time. The purée must taste intensely of celeriac — more so than any other preparation of the same vegetable. If it tastes primarily of butter or cream, the starting flavour was weak or enrichment was excessive. If truffle oil is used, add only off the heat, in drops, and taste immediately: the two aromatic families — celeriac's sulphur compounds and truffle's dimethyl sulphide — should amplify each other, not produce a single dominant note.