A person who failed to arrange an eiruv (and who resides in a city where an eiruv was not arranged for the residents) may not cook for himself or for other people. This prohibition applies even if the cooking is being done in the home of someone who did make an eiruv, using that person’s ingredients. It is also forbidden for other people to cook for him with his ingredients. He may, however, gift his ingredients to someone who prepared an eiruv and have that person use the ingredients to cook on his behalf. The cooking may take place in his home. In a case where there is no one available to cook for him, he may cook and bake a minimal amount for Shabbos. The minimal amount consists of one loaf of bread, one pot of food, and one candle for lighting. Contemporary poskim qualify that the candle should only be lit if there is no electricity.
[שו"ע תקכז, כ, משנ"ב נט ו־סב, ושעה"צ פח; וראה שם, פט; ביאורים ומוספים דרשו, 69]