Child born outside passport

[JamesNs]

I became a British citizen through naturalization before my child was born abroad, and my child is also a British citizen.

Can I apply for my child's passport within the UK, or must I apply from the country where my child was born?

[contorted_svy]

You can apply from the UK, but there may be questions as per to why you are doing so (how would you bring your child to the UK without a visa for example). You can apply from abroad, but be mindful that such applications can take longer to process.