1. Preheat the oven to 180˚C/gas 4.
2. Put the flour, buttermilk and puffed rice into three shallow bowls. Season the flour with salt and pepper. Add the garlic powder, onion powder, paprika and dried sage to the buttermilk and mix well. Crush the puffed rice with your hands so that the pieces are broken down slightly but not powdered.
3. Dip a piece of chicken into the flour so that it is completely covered. Remove and shake off any excess, then dip into the buttermilk. Allow any excess buttermilk to drip off, then put the chicken pieces into the puffed rice. Turn over to make sure they are completely coated, then place on a baking tray. Repeat with the remaining chicken pieces.
4. Put the tray into the preheated oven and bake for 25–30 minutes, until golden and cooked through, turning halfway through cooking.
5. Meanwhile, make the yoghurt dressing; mix together the yoghurt, crushed garlic and vinegar with a little salt and pepper. Taste and add more vinegar if needed.