Escape quotes correctly for looping over nested ssh commands

$ for server in $(cat servers); do echo $server $(ssh -A user@bastion "ssh -q -o UserKnownHostsFile=/dev/null -o StrictHostKeyChecking=no $server \"/bin/bash -c \\\"which mysqldump\\\"\" "); done

Output:

foo-2 /usr/bin/mysqldump

bar-4 /usr/bin/mysqldump

baz-12 /usr/bin/mysqldump

qux-3 /usr/bin/mysqldump

quxx-4 /usr/bin/mysqldump