The tomato slices glisten, raw, on top of a densely packed bed of leaves. There is something that might be grated carrot. It looks like a garden salad, separated into layers by lettuce and salad cream – or, perhaps, mayonnaise.

But is it a lasagne?

Coworker brought in vegan lasagna today and I’m ready to knock all that shit over. pic.twitter.com/eZWgkQNPWP — Peaches (@AristaFbabi) April 30, 2019

The low-quality phone snap of the alleged “vegan lasagne” that went viral on Twitter this week has fuelled the continuing culture wars over vegan food, put forward as evidence that it can never rival non-vegan fare.

“Coworker brought in vegan lasagna today and I’m ready to knock all that shit over,” fumed “Peaches” (@AristaFbabi) of Maryland, US, of her colleague’s lettuce-heavy contribution to a shared spread. Her tweet was favourited nearly 70,000 times and sparked a heated debate: can lasagne be vegan? And, if so – is that it?

“That’s a stacked salad,” responded one, drawing the support of nearly 10,000 people. The branded account of Stouffer’s – a Nestlé frozen foods brand that markets itself on the strength of “creamy, cheesy goodness” – was adamant: “Definitely. Not. Lasagna.” (“Neither is Stouffer’s,” retorted someone else.)

The vegan lobby, for the most part, agreed, responding along the lines of: “That’s not a vegan lasagne. THIS is a vegan lasagne.” They attempted to distance themselves from the pictured vegetable pile – truly, like something that might have been served at the Fyre festival – by pointing to more appealing examples of the form.

Jill Lucas, a nutritionist who goes by the name of Nutrient Nutter, says the photo made her smile, adding diplomatically that she applauds every effort to eat more healthily (and to cook for one’s colleagues). “My response, to my glance over the comments, is that we don’t know the nutrition or taste of the food from a picture. As with every diet, vegan food ranges from bad to incredible.”

“Raw salad versions” are a legitimate interpretation of lasagne, says Lucas, even if the pictured salad is “potentially not a visually appealing one. I would much prefer people supported and encouraged each other, as every step towards a healthier diet is wonderful.”

That said, Lucas’s own approach could involve lentils, wholegrain pasta sheets, aubergine, courgettes, sweet potato, peppers, crushed walnuts, parsley, tomatoes, paprika and that vegan staple: nutritional yeast. She says she would “lovingly” refer Peaches’ colleague to lasagne recipes by food bloggers Deliciously Ella, SweetPotatoSoul, FullyRawKristina, AvantGardeVegan and Bosh.

Day Radley, the founder of the Vegan Chef School in London, is quick to pour salt on the layered lettuce lasagne as being representative of vegan cooking. “I mean, to be honest, things like this are just funny,” she says. “If anybody is serious about trying vegan food, they know that that’s not really what it is.”

Perversely, it could even be good publicity for vegan diets, she says. “Anything that gets the word in front of more people is always a good thing … I think we should all have a sense of humour about this.” Humour is not something that vegans are renowned for, she admits – laughing – but, after 25 years of veganism, you learn “to have a bit of a banter about it”.

How would Radley approach vegan lasagne? “Well, not like that. Definitely not like that.” She says she would approach the challenge with cashew nuts (the basis of a lot of creamy vegan “chease”), fake meat or chopped mushrooms “for that umami flavour”. Her own recipe, however, is top-secret. “I’ve made some for Italian families, and they’ve loved it.”

“A lasagne has to be really decadent and unctuous, because that’s what a lasagne is, right?” says Radley. “A salad is a salad. A lasagne is a lasagne.”