Mix together warm water, yeast and sugar in a small bowl or cup and let rise in a warm place until foamy, 10 minutes.
Combine the flour and salt in a mixing bowl and make a well in the centre. Pour in the yeast mixture and the oil. Stir with a wooden spoon until the dough pulls away from the sides, then turn out on a floured surface and knead, adding flour if necessary. Knead until the dough is smooth.
Put the dough in an oiled bowl and turn to coat with a thin layer of oil. Cover with a damp tea towel and place somewhere warm to rise. Let rise until doubled, about 1 1/2 hours.
Punch down the dough, turn it onto a floured surface and shape into a ball. Let rise another 15 minutes.
Preheat oven to 180 degrees C.
Stretch or roll out the pizza dough and place on a circular pizza pan.
Spread with tomato passata and evenly distribute the slices of mozzarella.
Bake 20 minutes, then remove from over and immediately top with fresh basil leaves so they wilt a little. Enjoy!