So how did I end up sacrificing a summer Saturday to Westfield London, “the largest in-town shopping and leisure destination in Europe” from “the world’s largest listed retail property group by equity market capitalisation“? My first inclination is to do what any man would do in a similar situation: blame my wife, who was desperate to find a pair of shoes to wear to her sister’s wedding. With 29 shoe stores at Westfield I rated her chances of finding a suitable pair as high as 15 percent.

To you I will own up to ulterior motives. First, I was curious to see what was left of the summer sales at Vans, Geox, Desigual and Habitat. Secondly, I’d heard there was an Apple store. But mostly I was eager to try the foie gras-topped duck burger at Croque Gascon, the southwest French fastfood from the creators of the upmarket Club Gascon and its bistro-class spinoff, Comptoir Gascon. At Club Gascon I had admired the culinary wit of chef Pascal Aussignac. I loved his foie gras brioche club sandwich, which delivered its crunch via bacon sliced as thin as an estate agent’s sincerity. At the Taste of London festival in Regent’s Park I’d enjoyed a mini-version of his Croque Gascon duck burger. I needed to experience the real thing, sur place, and that necessitated my entering the mother of all shopping malls and coping with the sort of challenges I thought I’d left behind. Like mustard that won’t come out of its container.

When having frites I like to ask for both mayonnaise and mustard, mix the two and, voilà, I have Dijon mayo for dipping. At Croque Gascon I tore open and squeezed one of the yellow stick sachets they served me and only a tiny dab of mustard oozed out. I opened a second sachet and a third and still did not have enough mustard for my Dijon mayo.  I was furious.

Croque Gascon sources its mustard sticks from Soreal Ilou, a French producer of condiments for the food services sector. Two days after my scene at the mall I emailed the company and asked 2 questions: How many grams of mustard were there in a stick? What was the advantage of this small dosage? Within 2 hours I had a response from Jean-Jacques Gonzalez, Directeur Commercial Restauration. He noted there were 4 grams per stick and that although their Dijon was also sold in 12-ounce sachets, it was a strong mustard and 4 grams of it were often sufficient. In closing, Monsieur Gonzalez reasoned I must be an amateur de moutarde and generously offered to send me some Dijon sticks.  Great, I thought: if he sends me 30 I’ll have enough mustard to dress a salad.

I did get around to trying the duck burger accessorised with a silky escalope of griddle-fried foie gras. At first I admired the firm, almost crunchy texture of the chopped-duck patty, as I had at Taste of London. It did not measure up to the foie gras burger pioneered by Michel Trama at L’Aubergade in Puymirol, France or the foie gras-filled sirloin and short rib burger created by Daniel Boulud for db Bistro Moderne in New York, but it was hardly their equal in cost either. The price, recently dropped from £12.50 to £10.50, was unusually accessible for so silly an extravagance.

Soon, however, my outlook darkened. The foie gras had retained its texture, despite the grill cook’s best efforts to incinerate it, but so too had the duck burger. I yearned for something soft and juicy, such as a hamburger. Admittedly, by this point I was not in the best of moods. I had just discovered a fresh mustard stain over the right pocket of my pants. Just my luck: I can only manage to squeeze out a few measly molecules of mustard from 3 sachets and all of it ends up on my lap.

“You see,” I complained to my wife, pointing to the stains. “This is why I hate shopping malls.”