Mix the two kinds of flour together in a bowl, whisk in the grappa, then drizzle in the sparkling water. The batter should be smooth but not too runny. Add the bicarbonate then cover the bowl with cling film and rest for 30 minutes in the fridge. Cut the cheese into 2 cm cubes. Once the batter has rested, heat the oil in a large pan and dip one cube of cheese at a time into the batter, coating well and then lifting out with a spoon.
Drop the coated cubes into the boiling oil. Once golden, drain the sciatt and leave to dry on kitchen paper. Serve very hot, on a bed of dressed chicory.