In the meantime, put together your onions: Warmth a massive sauté pan over medium heat. As soon as very hot, insert 2 tablespoons olive oil. As soon as the oil is heated, include the onions and 1 teaspoon kosher salt. Prepare dinner onions, stirring each individual minute or two, right until a medium brown, virtually caramel coloured, about 25 minutes. [See Note at end.] Scrape onions on to a plate to amazing while you complete the bread.
Complete the focaccia: When the dough is doubled, line a 9×13 cake pan with parchment paper and drizzle 2 tablespoons olive oil above it. Do not deflate your dough, just scrape it onto the oiled parchment. Drizzle the major of the dough with another tablespoon of olive oil and use your fingers to dimple the dough, flattening it out. It is all right if it does not access the edges. Let the dimpled dough rest at place temperature for 15 minutes and warmth your oven to 425°F. After 15 minutes, dimple the dough only in which required a tiny further more into the corners. Permit relaxation for a closing 15 minutes in advance of scattering the leading with onions, poppy seeds, and a few pinches of salt.
Bake the focaccia: For 25 minutes, until finally deeply golden brown at the edges and throughout the top. Though it bakes, you can prepare any toppings you’d like to serve it with, this kind of as product cheese or butter, lox, thinly sliced tomatoes, cucumbers, onions, or capers.
To serve: Loosen the focaccia if it’s stuck in any put and slide it into a slicing board. Minimize into 12 squares, using a sharp knife to get by the onions on best without pulling them off, and replacing any that scatter. Try to eat correct away.
Do in advance: Focaccia keeps at space temperature for 1 to 2 times. Reheat on a baking sheet at 350°F for 10 to 12 minutes.
Take note: These are not caramelized onions we do not have to have 60 to 90 minutes more than small warmth with constant stirring. That is not how any ancestor of mine cooked onions. I’m intentionally employing a higher heat for more swiftly developed flavor. If they are not choosing up coloration by 20 minutes, bump up the warmth a little. If they are coloring far too fast to make it to 20 to 25 minutes, lessen the warmth. We want to halting shy of a darkish bronzed colour, as the onions will finish in the oven and we really don’t want them to burn off.