Tomatoes -- not the ones the American markets sell -- they may as well be cardboard (in the States you have to go to a farmer's market or grow your own or know someone who does), is one of life's little but wonderful pleasures.  In Vietnam you also have to avoid the markets and the imported tomatoes and go to one of the ubiquitous outdoor markets.  Since the market tomatoes are cheaper, easier to buy (there is a market one can walk to no matter where you are in the city) and much better tasting, for the life of me I don't see why anyone would want to buy an imported tomato.

I like to steam them a little to release the lycopene.