Triangle fan dome unwrapping Blender n00b here so sorry this is probably a simple question to fix.

I'm trying to unwrap a slightly domed triangle fan circle, but its breaking it up in the UV map instead of keeping it as a circle (which is messing the checker shading test up).

Any ideas what i'm doing wrong?

Many thanks.
Thanks @3fingeredfrog.

I used Pin (very useful tool!) combined with cube projection - unsure why this particular option worked, but it did.