Breakfast, lunch and dinner are all included during your time in North Korea. You should ensure your guide is aware of any special dietary requirements so they can reconfirm arrangements in advance. Shortages combined with the typical use of Korean cooking styles mean that there is a relatively limited range of food available.
Typical food consists of noodles, pickled cabbage, rice and meat. Barbecued meat is quite popular and is often barbecued at your table. Potatoes and eggs feature fairly widely in North Korean cuisine cropping up in all manner of dishes from soups to stews.
There are a few western food options now in Pyongyang and these restaurants can usually be visited if arranged with the guides in advance (additional cost). It is worth visiting the Vienna coffee house which is on the river side of Kim Jong-il square, for good coffee.
The local speciality is insam-ju, Korean vodka infused with ginseng roots, or rice wine. Locally made Taedonggang beer is very good – the brewery was purchased from Ushers in the UK and physically moved to Pyongyang – and some of the sojus are not bad either. Local alcohol is inexpensive; a 650ml bottle of beer is around $2.00. Imported beers, such as Heineken, are also available at similar prices. You should be mindful however not to drink to excess.
Drink plenty of bottled water which you can buy either from your hotel, your guide or from a reliable outlet. Be sure to also use bottled water for brushing your teeth.