Step 1

Heat the oven to 450°F with a rack in the lowest position. Line a rimmed baking sheet with kitchen parchment. In a large bowl, toss the onions with 2 tablespoons oil, half of the thyme, ½ teaspoon salt and 1 teaspoon pepper. Spread the onion mixture in an even layer on the prepared baking sheet, then evenly distribute the anchovies and olives over the top. Bake, without stirring, until the onions begin to brown and soften, 20 to 25 minutes.

Step 2

Meanwhile, on a well-floured counter, use a rolling pin to roll the dough into a 12-by-16-inch rectangle (the same dimensions as the baking sheet); work from the center outward to help ensure the dough is even. If it is resistant or shrinks after rolling, wait 5 to 10 minutes before trying again; if it is very elastic, you may need to give it a few rests. It’s fine if the dough rectangle is slightly smaller than the baking sheet.

Step 3

When the onion mixture is ready, remove the baking sheet from the oven; leave the oven on. Being careful not to touch the hot baking sheet, lay the dough over the onion mixture, gently stretching and tucking in the edges as needed so the dough fills the baking sheet. Brush with the remaining 1 tablespoon oil, then use a fork to poke holes every 2 to 3 inches all the way through the dough. Bake until the surface is well browned, 15 to 17 minutes.

Step 4

Remove from the oven and immediately invert a wire rack onto the baking sheet. Using potholders or oven mitts, hold the baking sheet and rack together and carefully invert. Lift off the baking sheet, then slowly peel away the parchment. Using a spatula, scrape off any toppings that cling to the parchment and return them to the pizza. Sprinkle with the remaining thyme and drizzle with additional oil.

Step 5

Optional garnish: Chopped fresh flat-leaf parsley