In a large bowl, combine the self-raising flour, Greek yoghurt and vanilla (if using). Mix until a soft dough forms.
Lightly flour your work surface and gently knead the dough until smooth. If it’s a little sticky, add a small amount of extra flour.
Divide the dough into 8 equal portions. Roll each portion into a rope approximately 15cm long, then join the ends together and gently press to form a doughnut.
Line your air fryer basket with a Multix Air Fryer Paper Liner Sheets and arrange the doughnuts in a single layer, leaving space between each one. Cook in batches if needed.
Air fry at 180°C for 8 minutes, or until puffed and lightly golden.
While the doughnuts are still warm, brush each one with the melted butter.
Combine the caster sugar and cinnamon in a shallow bowl, then roll each doughnut until evenly coated.
Serve warm for the best texture.
Recipe Tips
Don’t overwork the dough. Mix and knead just until smooth to keep the doughnuts light and fluffy.
Leave space between each doughnut. They’ll expand as they cook.
Coat while warm. Brushing with butter straight from the air fryer helps the cinnamon sugar stick perfectly.
Multix Tip A Multix Air Fryer Paper Liner Sheets helps prevent the doughnuts from sticking to the basket, making them easy to lift out while helping keep your air fryer cleaner.