What Makes a Croissant Good?

Croissants are often judged by how dramatic they look.

Tall layers. Huge honeycomb crumb. A cross section that opens like a piece of architecture. But when I started experimenting with this batch of croissants, that’s not what I was chasing.

I built this croissant with flavor in mind first.

The idea was to combine a very technical pastry with two things I genuinely enjoy working with as a baker: spelt flour and sourdough fermentation. Both bring something that standard croissant dough often lacks. Depth.

Spelt contributes warmth and a slightly nutty sweetness. Sourdough fermentation contributes acidity, particularly lactic acid, which has a way of amplifying the richness of butter.

Croissants are already a complex pastry. My curiosity was simple. What happens when we treat croissants like a fermentation project instead of just a lamination project?

Croissants as a System

One of the ways I approach baking through Breaducated is by thinking in systems.

Dough is never just flour and water. It is a set of variables interacting with each other.

Flour choice affects gluten strength. Fermentation shapes flavor. Butter percentage changes texture. Lamination determines structure.

For this experiment I adjusted several of those variables while keeping others consistent.

The dough contained 50 percent spelt flour. Instead of relying only on commercial yeast, the dough included sourdough starter. The dough was then allowed to ferment overnight in the refrigerator before lamination.

The lamination itself stayed relatively standard, with a 35 percent roll in butter and a traditional folding schedule of two book folds and one letter fold.

In other words, the structure of the croissant remained familiar, while fermentation and grain choice were allowed to shape the flavor.

The Role of Sourdough Fermentation

When people think about sourdough, they often focus on rise. But the most interesting thing sourdough brings to pastry is flavor chemistry.

During fermentation, the bacteria present in sourdough starters produce organic acids. One of the most important of these is lactic acid. Lactic acid is responsible for the yogurt-like tang that appears in many fermented foods. In laminated pastry it does something particularly interesting. It enhances richness.

Butter is already one of the dominant flavors in croissants. When lactic acid is present in the dough, that butter flavor becomes more pronounced and rounded. Instead of tasting simply fatty, the butter develops depth. This is one of the reasons cultured butter tastes more complex than standard sweet cream butter. Fermentation produces acidity that changes how we perceive fat. In this dough, the overnight fermentation allowed those acids to develop slowly before lamination even began.

Working with Spelt

Spelt changes the behavior of the dough in noticeable ways.

Compared to modern bread wheat, spelt has a softer gluten structure. During lamination the dough feels slightly more extensible and requires a gentler hand. Rather than trying to force the dough to behave like a strong bread flour, I chose to lean into that difference. The dough stretched easily during folds and rested well between turns. The layers remained defined, but the dough itself retained a tenderness that carried through the bake.

Spelt did not weaken the croissant.

It simply changed its personality.

The Bake

The first difference became noticeable during baking.

The aroma coming from the oven carried a deeper grain note along with the butter. Once the croissants cooled, the flavor of the spelt and the fermentation became clearer. When broken open, the exterior shattered cleanly while the interior remained soft and almost custardy.

These were not the tallest croissants I have ever made. The crumb was not the most exaggerated honeycomb structure either.

But they were deeply satisfying to eat.

The layers separated cleanly and the flavor had a richness that continued to develop by the next day. After resting overnight, the croissants softened slightly while maintaining their laminated structure. The lactic acidity from the fermentation also became more noticeable, giving the butter flavor even more depth.

They were also excellent for sandwiches.

Flavor and Aesthetics

This experiment made me think about how we evaluate croissants.

In a world where so much food is experienced through images, visual drama can easily become the standard for quality. Height and crumb structure often dominate the conversation.

But good is not always the same thing as impressive.

A croissant can look dramatic and still taste like very little. A croissant that is slightly shorter or more delicate might be the one you actually want to keep eating.

For me, this batch was a reminder that flavor deserves equal attention.

Variety in Baking

One of the things I love most about baking is that small changes in ingredients or fermentation can produce entirely new results.

Different grains bring different personalities to dough. Fermentation changes how we perceive sweetness, acidity, and fat. In this case, combining spelt flour with sourdough fermentation created a croissant that felt distinct without abandoning the structure that makes croissants what they are.

When we start thinking about dough as a system, experimentation becomes less intimidating and far more interesting. Sometimes the most memorable pastries are not the ones that look the most dramatic.

Sometimes they are simply the ones that taste the best.