I found several posts telling me to run several gpg commands, but they didn’t solve the problem because of two things. First, I was missing the debian-keyring package on my system and second I was using an invalid keyserver. Try different keyservers if you’re getting timeouts!
Thus, the way I fixed it was:
apt-get install debian-keyring
gpg --keyserver pgp.mit.edu --recv-keys 1F41B907
gpg --armor --export 1F41B907 | apt-key add -
Then running a new “apt-get update” worked flawlessly!