Soak Group 1 for 10 minutes and place into a 20L bowl. Whisk Group 1 to full volume for 8 minutes. Add Group 2 and whisk for a further 5 minutes. Gently fold in Group 3. Preheat oven at 120¼C and retain this heat setting. Bake time approximately 35 minutes. Switch off oven. Leave in oven with door ajar for a further 25 minutes.
Recipe percentages are on total batter / mix weight (100%)