Preheat oven to 400°F/200°C, combi steam setting. If you have variable steam settings, use 50%. If not, don’t worry! Just set to combi steam at the correct temperature and the oven will work out the steam for you.
Turn the dough onto a floured surface and gently knock out the air. Halve the dough and roll or stretch each piece into a 9x12 inch (23x30cm) rectangle. You’ll probably find the dough doesn’t want to stretch to this size immediately; if it keeps shrinking back when you’re shaping, cover and leave it for 5-10 minutes to allow it to relax, then try again.
Once the dough is shaped, mix the oil and garlic together and brush over the surface of each rectangle. Layer the ham, salami and cheeses over the top, leaving a 1 inch border on all sides.
3 Tbsp olive oil, 2 garlic cloves, 10 oz sliced ham, 10 oz sliced mild salami, 12½ oz mozzarella cheese, 7 oz Swiss cheese
Carefully and tightly roll up the dough into logs, tucking the edges in as you go and making sure the filling is fully enclosed. Take it slow; you want nice even stromboli logs!
Transfer each stromboli to a parchment lined baking sheet. Make 3-4 incisions in the top of each roll to allow steam to escape. Bake until the dough is golden and cooked through, about 25 minutes.