Mango tango honey toast (front) and spicy sausage honey toast at Aquarius. Photograph: Poppy Mcpherson/Phnom Penh Post

There’s a dessert bar in London called William Curley. I spent months dreaming about it. Dessert coupled with a dash of French je ne sais quoi. You start with Champagne granita. Then there’s a course of guava sorbet. Cherry blossom panna cotta. Pain perdu caramelised apples. Rum-soaked sultanas. Cremeux mille-fuille. And then, for the finale, petit fours to accompany the petit aperitif. All this I know from the website: I never made it to the place, and the memory of plans gone awry still rankles.

So when I heard a new dessert bar called Aquarius had opened near Tuol Sleng at the end of January, I was quietly thrilled.

The first signs weren’t encouraging. Pictures online advertised spaghetti bolognese and prawn cocktails. A slab of rib-eye steak. And, the horror, a post about “healthy lunch” options. Then, at the bottom of the page, a glimpse of the selling point – something called “honey toast”: a box shaped from soft white bread and smothered in sweet sauces, chocolate and ice cream. It’s big in Japan.

More ice-cream sandwich than Champagne sorbet, but enough to tempt me.

After all, some of my fondest food memories involve toast. Slices with melted butter as a childhood treat. Thin crusty sticks, “soldiers”, dipped in egg yolk. More recently, at Singapore Airport, after a gruelling, sleepless flight, two slices slathered in this sweet, strangely luminous butter was one of the best meals I’ve ever had. I had to go.

Note to the sweet-toothed: when trying to persuade someone to come to a dessert bar with you, the weekend is the best bet. When snack time is restricted to a bite for lunch and dinner, few would opt for sweets. Aquarius attempts to overcome this with its menu of uninspiring savoury options. On an after-work stop, we were told the honey toast was too sloppy to transport but picked up a few other goodies. Best was the sugary brownie, a little dry, but still chocolatey and with a crisp crust.

Returning the following afternoon, we were finally able to see Aquarius in full daylight. The purple and mint fairytale decor screamed Willy Wonka. The studded, velvety thrones with lilac mats draped over the arms would be equally at home in a porno. There were autobiographies by Oprah and Ellen Degeneres placed on mint green wooden shelves. Pushing back the wooden pen leading into the bathroom, I felt like a toddler on a trip to the farm.

Incredulity turned to child-like wonder when the honey toast arrived. We chose the “mango tango” type ($4.80) – though the macaroon honey toast and the bird nest honey toast intrigued. It was enormous. Imagine an entire loaf of sliced bread stacked up with a hollow carved to house cream.

“Do you know how to eat it?” the waiter asked – the service is suitably sugary. (The bill came in a little embellished box with pink hearts and the words “I love you”.) He showed me. First, pour a little honey on a plate. Then spoon off the ice-cream from the top of the bread fortress, dig in the hollow to find extra little pieces of spongy toast, pick one, spoon the cream back on and, finally, smear in the honey – there. Simple, with the cheap chocolate ice cream flavour of childhood – but delicious. Especially the soggy bits.

The savoury options are less inviting. Chicken wing lover honey toast and sunny-side up honey toast. My dining partner ordered the spicy sausage honey toast. Awful, even for a spicy sausage lover – each pale sausage carved to resemble a wilted flower, or a pork curly fry, placed in the corners of the castle with ketchup on the side.

We shared mine and took it with a pot of mixed fruits tea ($3.50) – strawberries, apple and pineapple soaked in syrupy dew.

By the end of the meal, I had reverted to childhood. Sugar high, hair disheveled, wiping crumbs from my face and lap.

I never made it to William Curley for fancy French dessert. But I did make it to Aquarius for cake crumbs on my face – and it was fun.

Aquarius, Street 95, corner Mao Tse Tung. Open 6:30am to 9:30pm Monday to Sunday.