Lunch/afternoon drink: Varosliget Kertem, Olof Palme stny. 1
Watch the sunset: Kopaszi gát, a small peninsula with a beach, park, and about a dozen restaurants. Accessible by ferry and tramway.
Lángos: fried savory dough, sour cream, garlic, and lots of cheese. I had it at the Great Market Hall/Nagyvásárcsarnok, which is also a must visit, but apparently it can be found for even cheaper in other spots. Vámház krt. 1-3
Dobos torte: What my Hungarian friend asks her mom to make for her birthday, this five layer chocolate and caramel cake is a classic. Avoid Café Gerbeaud, an overpriced tourist trap (sort of the Hungarian equivalent to Angelina) and try it at Ruszwurm Cukrászda, where it is much more authentic and reasonably priced. Szentháromság u. 7
Boat ride on the Danube: Instead of paying for a tour/cruise, take a public ferry, which can be paid for with your metro card, at the cost of about 2.50 euros.*
Kürtőskalács: sometimes called chimney cake in English, it comes in variations but the classic is bread/pastry rolled up, cooked over charcoals or wood, then sprinkled with cinnamon, sugar, and nuts. There are stands everywhere that sell it.
*Converted from the Hungarian Forint (HUF)