Method

• 1.
  Combine yeast and 600ml lukewarm water in a bowl, cover and stand for 10 minutes or until frothy. Combine flour and 1/3 cup (27g) salt flakes in a stand mixer fitted with the dough hook attachment. Add yeast mixture and oil, and knead for 10 minutes or until smooth and elastic. Transfer to a greased bowl, cover and stand in a warm place for 2 hours or until doubled in size.
• 2.
  Divide dough into six 280g balls, place on a tray, cover and chill for 24 hours (dough can be frozen for up to 6 months). Stand at room temperature for 1 hour before baking.
• 3.
  For the buttermilk ricotta, combine all ingredients in a medium saucepan over medium-high heat and bring to a simmer. Remove from heat and stand for 25 minutes. Strain ricotta through a sieve lined with muslin or a clean Chux cloth into a bowl and sprinkle with 2 tsp salt. Discard whey. Cover ricotta and top with a weight (a food can, for example). Chill overnight.
• 4.
  For the tomato passata, place tomatoes, sugar, oil and 1/2 tsp salt flakes in a saucepan over medium heat. Bring to a simmer and cook, stirring occasionally, for 40 minutes or until reduced.