Heat the oil in a deep fat fryer to 375 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 375 degrees F.) If you don't have a thermometer, a cube of bread will brown in about 3 minutes. Make the batter by adding the flour and salt to a mixing bowl and whisking in the beer. When ready, dip the candy bars into the batter. Drop the candy bars into the hot oil, and fry for 3 to 4 minutes, or until their exteriors turn golden brown. Serve the fried candy bars with a scoop of vanilla ice cream.