Saute mushrooms and onion in a little olive oil for 4 minutes on high heat.
Remove from heat and add spinach, salt, pepper and mix well then let cool. The heat from the onion and mushroom will cook the baby spinach.
On a floured surface roll out pizza dough, drizzle with olive oil, sprinkle with oregano and place chunks of fresh mozzarella evenly on dough surface.
Add sauteed mushrooms, onions and spinach then add artichokes cut in quarters and sprinkle with the diced pecorino al tartufo cheese.
Place pizza in a 500F oven and bake for 10 minutes or until crust is golden brown and cheese is bubbling.
Remove pizza from oven and cool slightly before cutting.