The Mishna Berurah (672:10) says
ואפילו ללמוד אסור משהגיע זמנה וכ"ש אכילה וש"ד ואפילו התחיל פוסק
Even to learn is prohibited once the time of lighting Chanuka candles arrives. And all the more so eating or other things. And even if he started he should stop.
I recall that when it comes to other similar Halachos such as eating [a meal] once the time of davening has come, appointing a shomer (someone to remind him later) helps.
I was wondering if the same applies with lighting the Chanuka candles. In other words, if someone appoints a shomer to remind him to light later, is s/he allowed to eat after the time to light has arrived?