Sift the flour, curry powder and baking powder into a large mixing bowl, and season with salt and pepper. Make a well in the center of the mixture and whisk in enough sparkling mineral water to make a very runny and smooth batter.
Fill a shallow saucepan with 2-inches worth of olive oil and set it over high heat.
Dip the zucchini flowers, in batches, into the prepared batter, shaking off the excess.
Carefully lower the zucchini flowers into the hot oil and fry, a few at a time, until golden brown.
Remove the flowers with a slotted spoon and then drain on a paper towel.