For the pizza:
1) Preheat the griddle to high.
2) Brush both sides of each pizza with the oil. Griddle until golden brown on both sides, about 2 minutes per side. Remove from the grill.
3) Mix together the caster sugar, cinnamon and star anise in a small bowl. Brush the tops of each pizza with the butter and sprinkle with the granulated sugar mixture.
4) Place back on the griddle, close the cover and cook for an additional 1 minute. Cut into quarters and drizzle with the warm chocolate sauce.
For the pizza dough:
1) In a large bowl stir together 75ml of water, yeast, and caster sugar and let stand until foamy, about 10 minutes. Stir in remaining 75ml water, 2 tbsps oil, 250g plain flour, cornmeal, and salt and blend until the mixture forms a dough.
2) Knead dough on a plain floured surface, incorporating as much of remaining plain flour, as necessary, to prevent dough from sticking, until smooth about 5 to 10 minutes. Form the dough into a ball.
3) Lightly cover the sides and bottom of a large bowl with oil, add the dough, turn to coat in the oil, cover and let rise in a warm place until doubled in size, about 1 hour.
4) Gently punch the dough down and divide into 4 equal pieces. Roll each piece on a lightly plain floured surface into a 25cm circle that is 0.5cm thick. Brush off excess plain flour and transfer the dough to a baking sheet, cover each circle of dough with plastic wrap and continue stacking rolled out pieces on top of each other. Wrap well with plastic wrap and refrigerate until ready to grill.