What is the southern German lye-glazed croissant called?

The southern German lye-glazed croissant is called a Laugencroissant.

The name combines Laugen, referring to the alkaline lye treatment, with Croissant. Before baking, the shaped pastry is dipped or brushed with a food-grade sodium-hydroxide solution. This creates the deep brown, glossy crust and the distinctive savory, pretzel-like flavor associated with lye breads.

Laugencroissants are especially associated with southern Germany and neighboring Switzerland. Swiss names include Laugengipfeli and Silsergipfeli, the latter linked to Sils in the Engadin. These regional terms can make the pastry seem like a different product, although they describe closely related lye-treated crescent pastries.

A Laugencroissant is not the same as a Cornetto, which is an Italian-style breakfast pastry, nor is it defined by a filling such as chocolate. Its defining feature is the alkaline glaze applied to laminated croissant dough before baking.