Marrow Pudding, Boiled or Baked

A bread-and-marrow custard from the era when beef marrow was a standard enrichment rather than a restaurant garnish. Nothing here is difficult, but the marrow and the measurements both need translating.

• The marrowSeven ounces of raw beef marrow will take several pounds of marrow bones, depending on their size; ask a butcher to split them lengthways. Chill the marrow hard before shredding — at room temperature it smears rather than cuts, and you want distinct flecks that melt through the pudding.
• Breakfast-cupfulA breakfast cup is about 8-10 fl oz, so three of them is roughly 3 to 3.75 cups of milk. Half a pint of crumbs is a volume, not a weight: about 1.25 cups of fine crumbs, whose weight will vary with how dry they are.
• Stale rollsCrumbs from a plain white roll or baguette, dried but not toasted. Commercial dried breadcrumbs are too fine and sandy; they turn the pudding pasty instead of light.
• Flavouring the milkPare the lemon zest in strips, heat it in the milk with the nutmeg, then fish the peel out before pouring over the crumbs. Grated zest left in gives a bitter edge over a two-hour cook.
• Sweeten to tasteFor this quantity, 3-4 oz (about half a cup) of caster or granulated sugar suits a dessert pudding. Start low and adjust.
• Baking temperatureThe recipe gives a time but no oven heat; for a pastry-lined custard, 325-350F is a workable modern setting for about an hour. The puff-paste lining browns better if the dish sits on a preheated baking sheet; a pastry-lined custard otherwise stays pale and damp underneath.
• Boiling means steamingBoiling the mould -- The original says boil, but a gentler modern approach suits an egg custard: butter the mould, cover it with pleated buttered paper or foil and tie it down, then stand it in a pan of simmering water reaching halfway up. Keep the water topped up for the full two hours; a hard rolling boil will curdle an egg custard.
• Testing itIt is done when the centre is just set and barely wobbles — around 170-175F on a thermometer. Serve warm, since the marrow firms up as it cools. Five or six portions, as stated.