1.Combine yeast, sugar and the water in a medium bowl of an electric mixer. Stand in a warm place 10 minutes or until bubbly.
2.Add flour, salt and 1 tbsp of the oil to the bowl; mix with a dough hook on knead setting 8 minutes or until smooth and elastic. Cover dough; stand in a warm place 30 minutes or until doubled in size.
3.Meanwhile, heat 1 tbsp of the oil in a large frying pan over medium heat; cook onion, stirring, 5 minutes, or until soft.
4.Preheat oven to 240°C. Oil two large oven trays.
5.Punch down dough with fist. Knead dough on a floured surface until smooth. Divide dough into four equal portions. Roll dough on floured surface into 30cm ovals; place on trays.
6.Drain peppers; pat dry, cut into quarters. Divide onion between bases; top with peppers, garlic and zucchini. Brush zucchini with remaining oil; season.
7.Bake flatbread 10 minutes or until bases are golden and crisp. Sprinkle with oregano; serve immediately.
If you don’t have a mixer with a dough hook, knead the dough by hand on a floured surface for 10 minutes by pulling and stretching the dough at every quarter turn. Flatbreads are best served freshly baked.Note