"I work at the expensive restaurant."
Translation:A drága étteremnél dolgozom.
dolgozok is an -ik verb.
Those traditionally take -m in the first person singular indefinite form, even though they are nearly all intransitive (and so can't take a definite form).
Some people use -k in that case anyway, while others consider that usage wrong. How wrong it sounds apparently depends on the particular verb; with some -ik verbs, -k is accepted a lot more than with others.