White Pizza with Anchovies, Artichokes, and Cauliflower

Modified from A Plum by Any Other Name.
Ingredients:
Pizza dough
1/2 can artichokes, chopped
1 red onion, very thinly sliced
~1/4 c. white vinegar
Kosher salt
~2 Tbsp. butter
~3 Tbsp. Italian parsley, very finely minced
2 cloves garlic, minced
~1 c, cauliflower florets, thinly sliced
Olive oil
Freshly ground black pepper
~1/2 Tbsp, fresh thyme, minced, plus more for garnish
1 1/2 cans anchovies
~1/4 c. parmesan cheese
~1/3 c. shredded fontina

Preheat the oven to 425 degrees.
In a small bowl, toss the red onion in vinegar with a little salt; set aside. Combine the butter, parsley, and minced garlic by kneading it a bit with your hands; place it in another small bowl and set aside. On a baking sheet, toss the cauliflower with some olive oil, salt, pepper, and thyme and roast until the cauliflower is golden brown, about 20-30 minutes.
Generously oil another sheet pan. Stretch and shape the pizza dough into a form of your choosing. Place the dough in the pan with the oil, stretching it until it's fairly even in thickness. Spread on the parsley butter. Add the red onions, shaking off any excess vinegar so they aren’t too wet. Cook the pizza for about 10 minutes. Then, add the cauliflower, artichokes, anchovies, fontina, and dusting of parmesan. Continue to cook for 5-10 minutes more, or until both the top and bottom of the crust is golden brown.
Sprinkle with more thyme and serve.