Us Brits always moan about the way Americans write the date. Shouldn’t it go from the smallest value to the largest, rather than month/day/year? Well, as much as I’ve had my gripes, today the system was appreciated. March 14 is 3.14 – the same numbers as Pi (π), a mathematical constant that helps you figure out the area of a circle. Which means today is Pi Day.

Every year, it’s celebrated by promoting the study of mathematics or by throwing pies at teachers. For me, it meant a trip to Pi(e) Face, a cute pie shop just south of Union Square that I’ve walked past hundreds of times.

I headed out just as the clock struck 3.14 on 3.14.

This holiday is particularly close to my heart because when I was in Year 9 (the last year of middle school), I was known among the boys on the bus for reciting pi to 10 decimal places in the corner at a party. While this never actually happened, I think it’s a pretty good indication of the reputation I had at that age. But I’d much rather that reputation than be known as one of the girls who boasted after necking a bottle of ‘vodka’ – that had actually been replaced with water – at parties.

So in a nod to those geekier days, I headed to Pie Face for a celebratory treat – and it was cute inside. Long tables, cool light fixtures and smiley and angry faces painted across the walls and pies.

Unfortunately, angry faces were also painted across the servers. I became pretty narked too when they told me they were out of every flavor pie that I wanted – they didn’t even have apple! Eventually I settled on the only fruit one they had – a mini lemon pie – and picked up a mini cheesecake pie for Ryan.

But I quickly learned that there is no such thing as settling for that lemon pie – that delicious lemon pie. It was basically a lemon posset in pastry – and what’s wrong with that? Tangy, creamy and sweet. And probably about 4,000 calories. But we’re celebrating right?

Unfortunately the cheesecake didn’t quite survive the walk home (I have no idea why they didn’t put the pies in a box) and I had to scrape the mush into a Tupperware.

But Pie Face is forgiven for its angry servers, poor packaging and mushed cheesecakes because of that lemon pie. The iced coffee was amazing too.

It’s definitely worth a trip if you’re near Union Square or one of their other locations. Next time I’ll try one of their savory pies. As I recite pi in the corner, of course.

Happy Pi Day!

Pie Face has eight locations in the city, including Midtown, Times Square, Murray Hill and Chelsea. Check out their website for more information and a menu.

For more information about Pi Day, check out CNN’s report.