What do you usually have for lunch?
How long does lunch take you during the week?
How long does lunch take you at the weekend?
Do you cook your own lunch during the week?
During the week, do you cook right before having lunch or do you cook it the evening before or even at the weekend?
Have you ever skipped lunch or any other day meal because of work?
Have you ever eaten lunch while working?
Get together with an English-speaking friend or relative and discuss the questions above. You may wish to read this article from The MailOnline beforehand to gain some insight on the topic.