Mix the flour and salt in a bowl. Combine the beer and egg yolks, gradually pour into the flour while mixing with a whisk, beat until smooth. The batter should be thick. Beat the egg whites until stiff, carefully fold into the batter.
Heat the oil to approx. 175°C. Dip the vegetables into the batter, drain and deep-fry for approx. 4 mins. until golden yellow. Remove and drain on paper towels.