I tested the edgy basics brand that NYC cool girls rely on for their uniforms — I get why it's so popular

If there's one thing I'm always on the lookout for, it's the perfect black tee. Marcella NYC's specialty is basics that are anything but basic — they always have an unexpected twist. That's definitely true of the Leonie Top, which features a sharp diagonal cutout at one shoulder for a peek of skin.

The first thing I noticed about this tee is that the French organic cotton jersey it's made out of is super soft. The dropped shoulders and boxy silhouette give this tee some modern appeal without taking away from its timelessness. I plan to wear this one with vintage-wash straight-leg jeans, leather leggings, and denim skirts.

One thing to note about this tee: It definitely has an intentionally oversized fit. I'm typically a size small, and I probably should've grabbed an XS. Whether you size down or not, though, just depends on personal preferences and how you plan to style the tee.

Another item I can never resist is the little black dress — and this V-neck number strikes all the right chords. It's effortless but elegant. It can be dressed up or down. And it has a universally flattering cut that hugs the smallest part of the waist while offering some forgiving flare from the hips down.

Again, the Emmy dress just feels expensive. The bodice is constructed with a structured European Ponte that boasts the perfect amount of stretch. The skirt, meanwhile, consists of lightweight European poplin cotton. The side zipper allows for easy on/off dressing, and I also appreciate the pockets for stashing my phone, lip gloss, and other essentials.

This dress fit true to size, and I'd argue it's suitable for a wide variety of occasions. For more casual hangs, I'll pair it with sheer ballet flats or leather slides and a denim jacket — but for date night, I'll dress it up with metallic block heel sandals and statement earrings.

I appreciate nothing more than a piece of clothing that does double duty — because it saves valuable space in my wardrobe (and my suitcase when I'm traveling). Not only that, but I can feel good investing in these types of pieces knowing I'll get double the wear out of them.

That's where the Belmont skirt comes in. Because it's thoughtfully designed with a foldover waistband and the perfect midi-long length, it can be worn both as a high-rise maxi skirt and as a midi strapless tube dress. The short slit is meant to be worn at the back, but I found that I could play around with the placement and position it front and center or even angled to the side of my leg.

The Belmont couldn't possibly be more comfortable — it's made with lightweight, breathable European French terry with a touch of elastane for stretchability. This is the kind of piece I can wear year-round, too: during the warmer seasons, I'll pair it with a cropped concert tee, and come fall and winter, I'll layer on a chunky sweater and some Chelsea boots.

I couldn't resist snagging another one of Marcella NYC's basics with a twist — and while the Felix top may look a simple crewneck tee in the front, it has a flirty crossover cutout design in the back. The Felix is made with the same ultra-soft 100% organic French cotton jersey as the Leonie and has a similarly slouchy fit. So, again, I'd advise sizing down if you want this to hang closer to the body. Pro tip: I also like knotting the extra fabric in the front to make this more of a cropped, fitted tee.

I've been pairing the Felix with faded, distressed black wash jeans and floaty knee-length skirts, but it's also a great layering tee under a blazer or cardigan.

Neglecting to mention Marcella NYC's shoes would be a cruel and unusual act of gatekeeping. The line features everything from chunky leather loafers and pointy mary-jane flats to strappy heeled sandals in vibrant hues and lace-up sneaker boots. But it was the chic Celeste Mules that instantly caught my eye. Mules have been having a major moment in recent months, and it's not all that surprising — they have the coverage of a close-toed shoe with the convenient slip-on style of a sandal, offering the best of both worlds and making them the perfect shoe for transitional seasons.

The Celeste, like many of Marcella NYC's other shoes, is handcrafted from 100% Italian leather. The pointed toe has a visual slimming effect on my foot, and the modest 1-inch kitten heel is super reasonable for day to day wear. I love that these shoes came with a dust cloth for storage and a replacement pair of heel caps to pop on for the sake of longevity (especially since I plan on wearing out these heels pretty quickly).

Very often, I find that pointy shoes feel suffocating on my wide feet — but that definitely wasn't the case here. The Celeste is among the most comfortable heels I own, and I was able to walk around in all day long with no aching, blisters, or other issues.

While these mules come in neutral go-with-anything shades like black and cream, I opted for the dreamy Santorini blue, which is surprisingly versatile. These add a fun pop of color to an understated fit, like a white tee and jeans, or a black cotton sundress.

Marcella NYC has a charming backstory. The cofounders, a husband and wife team, developed the idea for the line on their first date in NYC. Cofounder and creative director Siyana Huszar says fashion has always been in her DNA: her grandmother, Marcella — namesake for the brand — was a prominent designer in Bulgaria. After coming to the U.S. to pursue a corporate career, she realized she couldn't find clothing that truly reflected the sophisticated, modern New Yorker she aspired to be.

"That's when it hit me: my love for fashion and my personal frustration weren't just random — together, they were the perfect recipe for something bigger," she told Business Insider.

What sets Marcella NYC apart from other women's basics clothing brands is the dedication to both sustainability and social impact. The company uses ethical production practices, predominantly employs female production teams, sources only sustainable materials, and uses biodegradable packaging. Thanks to their leaner production process (which entails regularly restocking), they sell over 98% of what they make, which means less waste and a smaller eco-footprint. The company has also partnered with the global NGO CAMFED to support marginalized girls in Africa receiving a good education. Fashion with a cause? We love to see it.