1. Place Group 1 in mixing bowl.
2. Whisk on top speed for 5 minutes.
3. Add Group 2 and whisk for a further 2 minutes on top speed.
4. Add Group 3 and fold in by hand.
5. Pre-line a standard baking tray with a pre-baked 800 g sponge sheet.
6. Deposit yoghurt batter and spread evenly.
7. Place a second 800 g pre-baked sponge sheet on top.
8. Cover sponge sheet with greaseproof paper and press down with wire cooling tray.
Yield: Notes: By freezing overnight the slice cuts cleaner.