Izy Hossack is just 20 and still a student. The blogger tells Ella Walker how feeding herself at university has transformed how she cooks

Izy Hossack is celebrating finishing her second year at Leeds University, where she studies food science and nutrition, by publishing her second recipe collection, The Savvy Cook.

The 20-year-old foodie is best known for her blog, Top With Cinnamon, and matching Instagram account (229k followers and counting), where she posts beautifully-lit photos of oozing chocolate chip cookies and chunks of pecan-studded brownies.

The Savvy Cook, however, draws on how she went about feeding herself as a first-year student.

"I'd baked a lot, but I hadn't ever really cooked for myself throughout the whole week, and I had to go food shopping and budget," recalls Izy.

She started menu planning, pooling recipes from cookbooks and online to "keep it interesting", and the result is a stack of simple, intriguing recipes that help you plan ahead, cut waste and stick to your budget.

"I always do that thing where you buy a big bag of spinach because you don't want to buy the tiny one, and then it goes slimy and you never use it up," admits Izy, so she developed a leftovers section, where anything spare from one recipe can be cross-referenced and with other meals it'll fit into.

The book is also vegetarian, partly, again, to keep costs down, and partly because Izy watched a glut of Netflix documentaries on the environmental impact of dairy and meat farming. "If I'm going to buy meat, I want to buy high-quality stuff," she explains. "It's just really hard to fit that into your budget."

The Savvy Cook offers gluten-free and vegan slants on recipes too, so you can avoid that moment when "you're cooking for friends and one's vegan and one's gluten-free, and you're just like, 'I don't know what to cook you!'"

Food that's accessible, regardless of income or nutritional needs, is crucial to Izy's ethos - which means no obscure ingredients, either. In fact (supermarket-friendly) tahini and miso are as exotic as it gets, and they're featured in multiple recipes, so it's not like "buy this jar of expensive ingredient and let it sit in your cupboard for the next six months!"

Fads then, are a resounding 'No!'

"It's so enraging when you're a nutritionist and you read these headlines," says Izy, shooting down the coconut oil trend.

"It's so exclusionary - it's the whole organic vegetable thing, and superfoods. To be healthy, you have to have enough money to buy this thing, and buying plain tomato isn't good enough any more; you have to have the organically grown, biodynamic thing, with spirulina and you have to have turmeric in EVERYTHING you eat," she says, incredulous. "It's hard enough to get people to eat enough fibre and vegetables!"

Izy, who went to an all-girls school and started baking by herself aged around 10, might have written her first cookbook, Everyday Deliciousness, during her AS-levels, but that doesn't mean she was exempt from the problems and pressures around food.

"I went through a phase of maybe three or four years in my teens, constantly dieting and over-exercising," she remembers. "I used to think you could have anorexia, bulimia, or orthorexia [an obsession and anxiety over healthy eating] but now I realise there's more of a spectrum, and I definitely was on the spectrum of that. I wasn't getting admitted into hospital - I wasn't anywhere near that - but I definitely had issues around food.

"But I think, through blogging and speaking to other nutritionists, doing my course, the general backlash against clean eating, and body positivity coming out, it's given me more confidence, so now I'm happy.

"I'm going to eat butter; I'm going to eat cake; I'm a nutritionist - I don't care, I'm going to eat sugar, whatever! I know I'm eating a balanced diet and I'm happy with where I am, but I think we have to do a lot more in the future to help younger women, and show them you don't have to be eating 'clean' to be happy."

The Savvy Cook by Izy Hossack, photography by Izy Hossack, is published in hardback by Mitchell Beazley, priced £14.99. Available June 29 (www.octopusbooks.co.uk)