Preheat a deep fryer to 300 degrees F, or in a large heavy-bottomed saucepan, pour enough oil to fill the pan about a third of the way. Heat over medium heat until a deep-frying thermometer inserted in the oil reaches 300 degrees F.
In a bowl, mix the tempura mix and the beer. In a separate bowl, mix the string beans, heavy cream, flour, and salt. Add the bean mixture to the tempura mixture and coat the beans well. Lift the coated beans out of the batter, allow the excess batter to drip back into the bowl, and add the beans to the fryer and fry, in batches, until light golden brown. Drain the beans on paper towels, and serve immediately.
NotesThis recipe was provided by professional chefs and has been scaled down from a bulk recipe provided by a restaurant. The Food Network Kitchens chefs have not tested this recipe, in the proportions indicated, and therefore, we cannot make any representation as to the results.