This One Trick Will Help You Buy the Best Croissants in France

Step away from the curved croissants.

A visit to Paris inevitably means dedicating a chunk of time to worshipping at the altar of the croissant. To maximize your croissant experience, you need to be a discerning consumer — because even in their home country, not all of the flaky pastries are perfect.

According to a viral video I recently came across on Instagram, the shape of a croissant in France will tell you what it’s made of. More specifically, a straight croissant means the viennoiserie was crafted with 100% butter, whereas a curved version might be made with margarine or vegetable oil.

The claim is directly oppositional to my belief that all croissants — especially in France — are made purely with butter, and that croissants only come curved. The word "croissant" means “crescent” in French, and the croissant emoji is curved! But I suppose emojis aren’t the epitome of fact, so I decided to investigate in the name of journalism.

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Most online sources say there’s a law that dictates only all-butter croissants can be made straight, and ones with margarine or other fats in the dough must be arched. However the Confédération Nationale de la Boulangerie-Pâtisserie Française (or CNBPF, the professional organization that represents artisan bakers in France) confirmed for Food & Wine that "there are no specific rules on the shape of croissants."

The CNBPF does have a code of practice for artisanal viennoiserie and its composition, which states that a croissant can be made in either a curved or elongated (aka straight) shape; but the code does not mention the possibility of crafting a croissant with margarine, only butter. So the most traditional croissants should be made with butter.

That said, the difference between the composition of straight and curved croissants does appear to be popular wisdom in France today. It’s accepted as common practice, and as a good rule of thumb, you can trust that most straight croissants will be made entirely with butter. You’ll also likely notice that the croissants at a boulangerie are more likely to be straight, whereas the ones at a supermarket aren’t. Think of it as a baker’s code of honor.

A curved version of the pastry will look like what you probably imagine when someone says the word “croissant” — straight in the middle, with the edges turned inward. But a linear croissant won’t appear too unfamiliar, and you’ve likely seen one before. These pastries are often a little bit wider in the middle, sometimes shorter in length, and are shaped kind of like a football.

Croissants are a relatively young pastry in the history of France, and the version we know today was developed in the early 20th century. (Fun fact: croissants were created a few decades after a similar baked good, the Austrian kipferl, was introduced to the French — so you could technically say they come from Austria.) After margarine was also invented in France in the early 20th century, some bakers started using it to make croissants, because it’s a more shelf stable and affordable fat. This is how two different types of croissant developed: the croissant ordinaire and the croissant au beurre.

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As their names indicate, the croissant au beurre is made with butter, and the ordinaire with margarine. If you see both of them in a bakery, the former will likely be straight and the latter curved, as a sign to help customers differentiate — there will also probably be a small price difference between the two, since butter is more luxurious.

I asked French-born chef Nelly Azambre — one of three friends who opened Brooklyn French Bakers in New York City together — if this distinction between croissants was one she was familiar with. Azambre recalled her childhood, noting that "When I was little, at the bakery, there were two types of croissants. The curved croissant, which we called in Paris, where I grew up, the ordinary croissant, and of course, there was the straight croissant, known as the butter croissant... Naturally, my choice was solely the butter croissant!"

However the Azambre did also say that croissants ordinaire are becoming less common, as the variety is less popular than its buttery counterpart, and "Today, the croissant is generally straight." So it shouldn't be difficult to locate a butter-based pastry, and if you're ever in doubt about what a croissant is made with, just ask if it's "au beurre."

It’s not uncommon to make a puff pastry-style dough from margarine. Most of the frozen puff pastry brands you’ll find in the United States use this fat alternative because it’s cheaper. (For example, Pepperidge Farm’s puff pastry doesn’t contain any butter. If you want a dough that’s made with real butter, I suggest looking for the Dufour brand.)

A croissant or puff pastry made with margarine will still be close to what it’s trying to achieve. It will puff up and have those signature flakes. (Although for laminated dough you need to use baking margarine, which has a higher fat content, and is different from the tubs of margarine you buy in a store.) However, butter-based pastries will have an even flakier texture because of the fat’s lower melting point. And more importantly, margarine cannot replicate the taste of butter.

Margarine is made from mostly vegetable — and sometimes animal — fats like canola or corn oil, emulsified in water. If that sounds less delicious than butter, you’d be right! Because butter comes from real cream, it has a decadent, rich flavor that neutral oils just can’t compete with. So the next time you’re in France, it’s worth it to make sure you locate a straight-shaped croissant au beurre.