If a fat-free BLT sandwich sounds too good to be true, ask New York celebrity chef David Burke to make one. His version would go something like this: Lettuce, tomato and a few sprays of bacon on toast. Burke, chef at the upscale Manhattan eatery davidburke & donatella, has come out with fat-, calorie- and carbohydrate-free "flavor sprays" for regular Joes who are watching their weight or are time-crunched in the kitchen. There are 18 savory and sweet sprays in the line, from smoked bacon to banana split. A dozen more flavors are planned, including wasabi, sausage and peppers, and...