It’s been quite a week for solo operas. On Saturday, Ruth Strutt premiered Possession at Qtopia, Allan Clayton has just embarked on a tour of Schubert’s A Winter’s Journey for Musica Viva Australia, and now Deborah Humble is taking over kitchens from the Hunter Valley to Melbourne in Bon Appétit!

This performance, staged at a private home in Woollahra, is a real treat, bringing one of Australia’s and the world’s most accomplished mezzo-sopranos up close and personal.

The last time I found myself in such an intimate gathering was at a Lieder recital in Europe, and the amplified sense of expectation is just the same. Likewise, the feeling of exposure you get when an opera singer of Humble’s calibre sings directly to you is undeniable.

Except that it isn’t Humble who descends the staircase, welcoming us with a familiar hoot. It’s Julia Child – the pioneering chef who introduced French cuisine to American households through the medium of television and her cookbook, Mastering the Art of French Cooking.

As Humble weaves her way through the audience to the kitchen where she will proceed to make Le Gâteau au Chocolat l’Éminence Brune, her resemblance to Child is uncanny; so exact are her look, her mannerisms … and that voice.

Deborah Humble in Bon Appétit! Photo © Magnetic Shots

Composed in 1989 by Lee Hoiby, Bon Appétit! was created as a vehicle for Jean Stapleton, who spent several years performing it throughout the United States as part of a double bill that also included Hoiby’s Italian Lesson.

Child went to see the Los Angeles premiere and gave it her blessing, famously saying, “I only wish I could have sung it like that when I originally did it.”

Given its subject matter, it is easy to underestimate the complexity of Hoiby’s vocal writing, which sits somewhere between The Medium by Menotti, his teacher, and Schoenberg’s Pierrot lunaire – the combination of parlando and Sprechstimme capturing the operatic cadences of Child’s unique speech patterns.

It’s complex stuff, made all the more challenging by the fact that it needs to be perfectly timed with the various steps in Child’s cake recipe that uses cornstarch and the all-important cream of tartar.

Bon Appétit! sets the famed cook’s own words, drawn from two episodes of her 1960s TV show, The French Chef – Hoiby’s partner and librettist Mark Schulgasser conflating Child’s cake-baking instructions with her egg-white-beating race against an electric mixer. Of course, she whisks her way to victory.

Apart from quoting La Marseillaise – a nod to Child’s time in France and an appropriate call to arms as she mentions the need for “a battle plan” when tackling the hidden complexities of chocolate – Hoiby’s piano score largely comprises various figures, such as a whole-tone scale for stirring the semi-sweet and bitter chocolate together.

There are also motifs for preheating the oven, buttering the cake pan, dissolving the espresso, the aforementioned beating and subsequent folding in of the egg-whites, and finally glazing.

Deborah Humble in Bon Appétit!. Photo © Magnetic Shots

As the timing for these processes obviously varies from one performance to the next, Hoiby allows for optional repeats and ‘vamping till ready’, and this is where previous interpreters have sometimes come unstuck – the signalling between the singer and pianist becoming imprecise, and the vocal part and accompaniment falling out of sync.

This is usually due to the performances being one-offs, with neither singer nor pianist having the time to settle into such a difficult routine.

Fortunately, that is not the case here. Humble and pianist Sharolyn Kimmorley’s performances are perfectly timed, their parts seamlessly integrated with the cooking tasks.

Humble makes light work of the score and Child’s characteristic pitch shifts. She effortlessly plumbs the depths of the TV chef’s mutterings in the lower register before soaring to a gloriously lilting “soufflé” that lingers in the air.

Humble’s perfect vocal performance is matched by her acting portrayal of Child, whom she inhabits totally. More than just a loving impersonation or the skin-deep mimicry of an SNL sketch, it captures Child’s joie de vivre, fearless bravado and self-deprecating humour.

Humble’s Child is no Wagnerian battleaxe, however, and beneath her devil-may-care attitude, we catch a glimpse of her struggle to overcome her own self-doubt when something doesn’t go according to plan.

Nor does Humble resort to caricature like some of her predecessors, whose interpretations have sometimes bordered on Fanny Craddock, with hidden assistants revealed behind the kitchen bench.

There’s none of that here, and apart from the clapperboard at the top of the show and the obvious cake prepared earlier, the performance unfolds like one of Child’s 30-minute television programs, without anything to detract from the rapport she builds with her viewers.

Naturally, the finished product is wonderfully imperfect and ever so slightly lopsided – just as it was in the original television program – but the inquisitive members of the audience who invade the kitchen all agree it’s finger-licking good.

Julia Child would be proud.