If you order a burger and the server pivots away without asking you how you want it cooked, that is already a bad omen. Restaurants that don’t elicit doneness orders may not think a burger is worth the bother. (A waiver for the doneness designation should only be granted to burger joints whose patties are flat in shape, under 6 ounces in volume or under £6 in cost.)

If you insist on telling the swerving server how you want your burger cooked and he or she responds with an ambiguous nod, then it is probably time to run for the hills.

Mrs youngandfoodish and I witnessed these two early indicators of a subprime burger at The Canonbury in N1. Over the weekend I’d been scouting locations for upcoming #BurgerMonday meetups and eatups and had heard this completely renovated and upgraded pub was sourcing its mince mix from two of London’s best butchers. The refurbished garden terrace behind this Georgian building in leafy Islington seemed a ideal setting for a juice-dripping jamboree.

I halved the Canonbury burger we’d ordered medium rare to inspect and photograph the interior and reference its coloration to the burger doneness colour strip I carry with me at all times. Sadly, the chef had either overcooked the burger or photoshopped it to remove its pinkness.

Rather than ask the server to return the medium-well burger to the open kitchen I decided to do so myself. I brought the burger, with its serving board, to the kitchen, laid it down on the pass and, in the gentlest tone I could muster, asked the chef if she would agree this burger was not medium rare.

In the gentlest tone she could muster she noted that you can’t touch-test a burger for doneness as you can with a steak (true) and that  it’s difficult to get it right (also true). You had to accept that a burger might be darker or redder than was desired.

I nodded, took a deep breath and feigned a retreat. “But,” I continued, trying my best not to sound like a pushy New Yorker, wouldn’t you get acquainted with the intensity of your grill after cooking 20 burgers? Wouldn’t you gain familiarity with the outer appearance of the burgers as they cooked on the grill and what the darkening shades said about their interior colour?”

“You could say that,” replied the chef, with vinegary sarcasm. This time I did retreat, thinking it best not to inquire if she’d made this alarmingly compact, Jack Dee-dry, hockey puck of a grey-as-the-Swansea-dusk hamburger with frozen meat. I was thinking ahead: I wanted to alert you to the early warning signs of a subprime burger and preferred to type it out with unbroken fingers.