cakes, pastry
餻 centers on baked flour-based foods: cakes and pastry. It refers to sweet or savory baked goods made from dough or batter.
餻 combines the food radical 飠 with 羔 (lamb), which likely contributes the sound. The character originally referred to a type of cake or pastry, possibly made with lamb fat or associated with the sound of 羔.
The food radical 飠 on the left suggests something edible, and the right side 羔 looks like a lamb. Imagine a lamb-shaped cake or a pastry made with rich lamb fat: 餻 is a cake or pastry.
For コウ, picture a cake so good it makes you say "coo!" in delight: coo -> コウ, and the cake is the pastry 餻.