Canelés de Bordeaux
If using fine salt instead of kosher, use 1/8 teaspoon instead of 1/4 teaspoon.
Greasing the muffin tins with beeswax/butter is essential to achieve the classic texture and crispy exterior. Use only pure food-grade beeswax without any additives.
These stay crispy for only about 8 hours. So, fair warning if you plan to make them a day ahead. I've never tried to re-crisp them.