How to thicken a sauce

March 29, 2012

Lamb shanks.

Good gravy ... Cornflour can be used but proceed with caution. Photo: Marina Oliphant

Richard Cornish answers your vexing food questions.

Can I use cornflour instead of plain flour to thicken a sauce?
M. Derring

Grandmother Cornish could cook a dozen dishes very well. One was lamb shanks slowly simmered for several hours with bay and nutmeg. Refrigerated overnight, the solid layer of fat on the meat jelly was removed and the jellified juices and meat heated again. To thicken it, she poured in a slurry of real cornflour (cornstarch) and water, and mixed it once. She let it bubble for a minute without further stirring. When cornstarch is heated, the molecular chains unravel and team up with other molecules to form a network that traps water. If heated or stirred too much, it can thin out again. Nana spooned the shanks and sauce over plates of hot mashed potato. The gravy was lip-smackingly thick. So, yes, you can use cornflour as long you don't beat it or overheat it, and you use half as much as wheat flour.

Where can I buy citrus caviar?
P. Bright

When settlers first arrived in the Northern Rivers area of New South Wales, they tended to chop down every living thing in front of them - except one tree, Microcitrus australasica. This was a native citrus that produced a crop of small sausage-shaped fruit between December and June. Citrus are native to Australia, with four main varieties found in the north of the country. We now call the ones found between Ballina and Mount Tamborine ''finger limes'', while some restaurants refer to their flesh as ''citrus caviar''. The ''caviar'' part of the term refers to the juice vesicles - small teardrop-shaped pearls inside citrus. These little ''caviar'' have a firm texture on the tongue and, when crushed in the mouth, release a pleasing amount of sour citrus juice and are wonderful with raw oysters and white fish ceviche. Finger limes are available in several colourful varieties from Damian Pike at the Prahran Market. For other areas, visit wildfingerlime.com.

How do I turn a leg of pork into a leg of ham?
J. Coghill

You can salt a leg of pork for 10 days, then hang it in a cold, dry place for several months to make a decent prosciutto. You can brine a leg of pork for several days and bake it to make quite a lovely west country ham. I refer to the recipes in Hugh Fearnley-Whittingstall's The River Cottage Meat Book for this. I once tried to make a smoked ham myself, which involved ''smoking'' a leg of brined pork swinging from a rocket-shaped tomato trellis over gum chips in a brazier. The result was a complete balls-up, with a salty, dry and inedible ham. It was a miserable Christmas. Making smoked ham is an arcane art that takes years to perfect and is best left to the experts. If you're really determined, take an apprenticeship in a good butcher shop or - for quicker results - book into a ham masterclass with Rodney Dunn at the Agrarian Kitchen in Hobart later in the year (theagrariankitchen.com). Or buy Meat Smoking And Smokehouse Design by Adam Marianski and Stanley Marianski from Books for Cooks in Fitzroy.

Where can I buy faggots?
A. Blankfield

Thanks for this query, as well as all the photos of the vegetables from your garden that have grown into rude and amusing shapes. Faggots are parcels of seasoned pork meat and liver, wrapped in caul. You can buy them from Rob's British Butchers (177 Lonsdale Street, Dandenong, $10 box of six). Owner Rob Boyle reckons they're called faggots after the faggot of herbs used in the cooking of the liver. The word faggot comes from old Italian fagotto, meaning bundle of sticks. The Italian liver sausages at Gervasi Continental Grocer (870 Sydney Road, Brunswick) are called salsicce di fegato. The Italian word fegato, however, comes from the Latin for fig because the Romans used figs to fatten geese. Salsicce di fegato will be available when the winter pig-killing season begins and will be about $12/kg.

Send your food queries to brainfood@richardcornish.com.au

How do you thicken sauces? Use the comment function to share your tip.