During which phase of Macaron preparation should the mixture be allowed to dry a bit?

Allowing the macaron mixture to dry a bit before baking is an essential step in achieving the desired texture and appearance of the final product. This drying phase helps form a skin on the surface of the batter, which is crucial for proper baking. When the macarons are piped onto the baking sheet, letting them sit for a period allows moisture to evaporate, promoting a smooth and glossy surface.

This skin formation is vital for developing the characteristic 'foot' of the macaron during baking, which occurs when the steam generated from the batter expands under the surface. If the mixture is too wet, it may not rise properly, leading to flat cookies instead of the desired airy texture.

In comparison, the other phases mentioned do not contribute to this drying process. Cooking the sugar syrup is part of preparing the meringue or the batter but does not relate to drying. Mixing the ingredients is necessary for combining them, but the drying skin forms afterward. Finally, cooling occurs after baking, which is unrelated to the drying process required for the batter. Hence, allowing the mixture to dry a bit before baking is a crucial step in macaron preparation.