In a large bowl, stir 240 ml warm water with 1 tsp granulated sugar and 7 g active dried yeast; leave for 5–10 minutes until foamy.
Stir in 2 tbsp olive oil and 1 tsp salt, then gradually add 300 g plain flour, mixing until a shaggy dough forms.
Tip the dough onto a lightly floured surface and knead for 5–7 minutes until smooth and elastic.
Lightly oil a clean bowl, place the dough inside and turn to coat. Cover with cling film and leave in a warm spot for 1–1½ hours until doubled in size.
Meanwhile, make the sauce: combine a 425 g tin of crushed tomatoes with a minced garlic clove, 1 tsp dried oregano, ½ tsp salt and ¼ tsp freshly ground black pepper. Set aside.
About 30 minutes before baking, place a pizza stone or an upside-down baking tray in the oven and preheat to 250 °C (230 °C for fan ovens).
Knock back the risen dough, then roll or stretch it into a 30 cm circle on a floured surface.
Transfer to a piece of baking parchment or a floured pizza peel. Spread the sauce evenly, leaving a 1 cm border.
Scatter 225 g shredded mozzarella over the sauce, then top with 85 g sliced pepperoni.
Slide the pizza (on the parchment, if used) onto the hot stone or tray and bake for 12–15 minutes until the crust is golden and the cheese is bubbling.
Remove from the oven and rest on a wire rack for 5 minutes before slicing and serving.