I did a couple of articles on this a few years back, which I unfortunately can't find right now. One described the use of "subterrenes" to bore habitats on the Moon, like you describe. This is another good reference on some of the work that has been done in this area. The info on subterrenes is real. The crackpot stuff on "secret tunnels" is not.

Another article proposed using large lunar lava tubes for on-site shielding by putting pressurized huts inside them. Very little excavation required. This is a good reference on this subject. I always thought this was the most practical solution if a suitable site could be located.

It is interesting that such tubes may also exist on Mars.