In a large bowl, combine the self-rising flour and fine salt.
In a separate jug, whisk together the egg, sriracha sauce, and chilled sparkling water.
Add this egg mixture to the flour mixture and whisk until just combined.
Preheat the Air Fryer:
Preheat your 5- or 6-quart air fryer to 350°F for 3 minutes.
Prepare the Bread Crumb Mixture:
Place the panko bread crumbs in a separate bowl.
Drizzle a bit of extra virgin olive oil over the bread crumbs.
Using your fingertips, rub the oil into the crumbs until they are well combined.
Coat and Cook the Vegetables:
Working with one vegetable piece at a time, dip it into the batter, allowing excess to drip off.
Then, coat the vegetable in the bread crumb mixture.
Place the coated vegetable on a tray lined with parchment paper.
Continue coating until you have 6-8 vegetable pieces ready to cook.