If you’re making canelés outside of France, you’ve probably run into the T45 flour question. Most traditional recipes call for it, but it’s not easy to find in the US or many other countries. So what’s the best substitute?

What is T45 Flour?

T45 is a French flour classification based on ash content — the mineral residue left after incineration. Lower T numbers mean more refined flour with less bran and germ. T45 is the most refined French flour, with a very fine texture and low protein content (around 7.5–9%).

For reference:

  • T45: ~7.5–9% protein, very fine — pastry flour
  • T55: ~9–11% protein — French all-purpose, used for baguettes
  • T65: ~11–13% protein — closer to American bread flour

Is Cake Flour the Closest Sub?

Yes. Multiple baking sources confirm that American cake flour is the closest widely available equivalent to T45:

  • Protein content lines up well: cake flour runs about 7–9%, right in the T45 range
  • Both are finely milled, producing smoother batters
  • Italian Tipo 00 flour is also comparable, though it can vary more in protein content depending on the brand

All-purpose flour (10–12% protein) is noticeably higher in protein than T45. The extra gluten development can make baked goods chewier and denser — the opposite of what you want in delicate French pastry.

Does It Matter That Much for Canelés?

Here’s the thing: canelé batter is mostly milk, eggs, and sugar. Flour is a relatively small component (around 285g flour to 675mL of dairy in a typical batch). The custard-like interior texture comes primarily from:

  • The egg-to-milk ratio
  • The long overnight batter rest (which hydrates the flour and lets gluten relax)
  • The high-heat bake with beeswax-coated molds

Many well-regarded canelé recipes — including ones that produce excellent results — use straight all-purpose flour without any issues. The dark caramelized crust comes from the beeswax coating and the initial blast of high heat, not the flour type.

That said, cake flour does produce a slightly softer, more custardy interior because less gluten forms during mixing. If you’re chasing that ultra-tender, almost creamy center, it’s worth using.

The Cornstarch Hack

If you want to get even closer to T45 with American flour, there’s a well-known trick: for every cup of all-purpose flour, remove 2 tablespoons and replace them with 2 tablespoons of cornstarch. This effectively lowers the protein content and mimics the finer texture of T45.

You can do the same starting from cake flour if you want to go even lower protein, but at that point you’re probably overthinking it.

Bottom Line

  • Cake flour is a solid, reliable substitute for T45 in canelés
  • All-purpose flour works fine too — canelés are forgiving on flour choice
  • If you want to split the difference, use the cornstarch swap with AP flour
  • The overnight rest, egg ratio, beeswax, and oven temperature matter far more than flour type for canelé success

Sources