Heat the vegetable oil in a deep heavy-bottomed saucepan, until a breadcrumb sizzles and browns when dropped in it. (CAUTION: hot oil can be dangerous - do not leave unattended!)
Place the flour, cumin seeds and sesame seeds into a large bowl and mix together.
Add the sparkling water and whisk vigorously to form a batter.
Dip the broccoli florets into the batter and carefully place into the hot oil and deep-fry in batches, so as not to overcrowd the pan. Carefully remove with a slotted spoon and drain onto kitchen towels.