Honestly, I didn’t have high hopes for this restaurant.
Not because of Onja itself, but because I have unusual allergies – to alliums – and I’m typically either told I can’t eat anything at all, or I’m given something dry and uninspiring whilst being made to feel like a burden.
But as I have an obsession with East African chapati, and Swahili cuisine is my fave, I knew I had to check out Cardiff’s newly-opened Tanzanian restaurant regardless.
East African food is extremely rare in the UK and, as a collector of experiences, I knew even if I could only eat the chapati it’d be worth it.
I messaged Onja to ask if they would be able to accommodate my allergies and the owner, Justina, responded quickly. She told me if I gave her a few days’ notice of when I wanted to eat there she’d prepare something for me.
This already placed Onja in a different league to most restaurants in the UK, but I didn’t want to get my hopes up.
When it comes to eating at restaurants with an allergy to onion and garlic, I’ve learnt to keep my expectations low.
A few days later, my laptop died and as I’m currently in Wales I had to head to the Apple store in Cardiff, an hour away from where I’m staying. I messaged Justina again, apologising that I wouldn’t be able to give her much notice and asking even if I only ate chapati would I be able to eat there that evening.
Her response was reassuring and she even gave me her number, telling me chapati can sell out on Saturdays so she’d keep some aside from me.
For the first time in a long time, I began to feel excitement about visiting a restaurant.
Location
Onja is well-situated right in the heart of Cardiff City Centre, on Barrack Lane.
If you know Cardiff, it’s right behind where Debenhams used to be; if you don’t it’s behind the food court area of St David’s 2.
The vibrant sign stood in relief to the gloomy evening; the windows were adorned with African print, zebra and the words Hakuna Matata (no worries).
It was the embodiment of Karibu: I felt welcome before I even stepped inside.
Service
I was greeted warmly by two men at the counter; they instantly put me at ease. I’m no stranger to eating alone, and often prefer it, but my social anxiety means I can feel awkward in unfamiliar environments.
As I’d been in contact with Justina I asked them if she was there. One of the men went to fetch her and the moment I saw Justina I knew that I would not regret coming to Onja: her huge smile told me everything I needed to know and she hugged me like I was an old friend.
After a brief chat about my laptop woes and my allergies, she told me she’d whip me something up and I took my seat.
I was brought a huge jug of water and offered the choice of ice, or no ice (which is rare, but great attention to detail in terms of people’s differing preferences).
Justina served me herself but all the staff were attentive, friendly and polite.
Ambiance
The restaurant has a range of seating types, including a booth below a life-like mural of Mount Kilimanjaro. My seat was incredibly comfortable and the place has a cosy vibe.
Prominently displayed on the counter was a sign stating that allergies are catered for, which was reassuring.
Tanzanian art adorned the walls and the music instantly transported me back to my travels in East Africa: for me, it felt like coming home.
It did not feel like I was sitting in a Tanzanian restaurant in Cardiff! It felt like I was back in my favourite part of the world. If you’ve not yet been fortunate enough to experience East Africa then Onja will truly give you a taste of Tanzania; a glimpse into another culture.
And at the heart of any culture is their food.
Food
My Sam-safe meal was an off-menu creation.
I was given nyama choma (barbecued meat – in this case, lamb) with my requested chapati and a salad of carrot, green pepper and cucumber in lieu of the traditional kachumbari, which contains onion.
The meat was tender and perfectly spiced; the salad fresh. And the chapati? The chapati made me do a happy dance in my seat!
Justina excitedly told me that she was already thinking of how she could prepare me future meals so that they were allium-free and I cannot express how much this meant to me: anyone with an allergy knows how rare and how precious this is.
She’d already served celiacs and gluten-free customers, as well as vegetarians and vegans, but – as with most places – she’d never encountered anyone with an allium allergy before. We’re a rare breed.
I’m already excited to be able to have soup, stew or curry. And I know that Onja is going to be a place I’ll visit regularly, wherever I am based. I’ve lived in London for the past eight years and Onja would have been worth a journey from there.
To my knowledge, it’s also the ONLY Tanzanian restaurant in the UK.
London has lots of West African places, Ethiopian and Eritrean restaurants but other African cuisines are less common. For East African – or Swahili – cuisine, I only found two Kenyan and one Ugandan restaurant. And the latter told me they couldn’t accommodate my allergies.
And people are truly sleeping on Swahili cuisine. Just trust me on this.
After my meal, Justina offered me complimentary spiced masala chai and more chapati, which was an offer I couldn’t refuse! The tea was the perfect antidote to the miserable winter weather outside.
The Verdict
It’s going to be no surprise if you’ve read this far that I am recommending that you run, don’t walk, to Onja!
Hands down, it’s been my best experience of 2025 to date and I started the year travelling.
If you’ve been following my East African travel stories and you’re in the UK this is the easiest way to experience a little of what I’ve been describing without catching a plane – or stepping too far out of your comfort zone – and many of you have talked about the way I’ve described the food there makes you feel that you can taste it. Well, now you can!
If you’re new here, you can read about my travels in East Africa in my book, To Live Not Exist. It’s available on Amazon worldwide (just search the name) or you can click here for the UK version.
Justina’s son, Tariq, has also written about his own travels in Tanzania and you can buy his book, Brothers in the Wild: Serengeti Safari Adventure, here.
Justina grew up in Tanzania and has lived in Cardiff for 25 years. Having always dreamed of opening a restaurant, it took her many years to make that dream become a reality: Onja opened in December 2024. She told me she hopes she’s done the right thing.
She absolutely has.
If you’re looking for great, affordable, food, or an experience – or both – then this is the place for you. Onja means taste in Swahili – and it truly is a taste of Tanzania.
Opening Hours:
Monday – CLOSED
Tuesday – CLOSED
Wednesday – 12pm – 8pm
Thursday – 12pm – 8pm
Friday – 12pm – 9pm
Saturday – 12pm – 9pm
Sunday – 12pm – 8pm
Contact:
You can find out more about Onja, or contact Justina, here:
Average cost:
£ – ££
Rating:
N.B. I was not asked to write this review, nor did I receive payment. I did get a discount on my meal but there were no conditions attached and I have written this review because I wanted to: Onja deserves to be placed on the map.