Meanwhile, prepare your onions: Heat a huge sauté pan over medium heat. The moment incredibly hot, include 2 tablespoons olive oil. After the oil is heated, add the onions and 1 teaspoon kosher salt. Cook dinner onions, stirring every single minute or two, until a medium brown, nearly caramel colored, about 25 minutes. [See Note at end.] Scrape onions onto a plate to great whilst you finish the bread.
Finish the focaccia: When the dough is doubled, line a 9×13 cake pan with parchment paper and drizzle 2 tablespoons olive oil over it. Do not deflate your dough, just scrape it on to the oiled parchment. Drizzle the top rated of the dough with one more tablespoon of olive oil and use your fingers to dimple the dough, flattening it out. It’s alright if it doesn’t arrive at the edges. Permit the dimpled dough relaxation at place temperature for 15 minutes and warmth your oven to 425°F. Soon after 15 minutes, dimple the dough only the place wanted a little more into the corners. Let relaxation for a last 15 minutes ahead of scattering the top rated with onions, poppy seeds, and a few pinches of salt.
Bake the focaccia: For 25 minutes, right until deeply golden brown at the edges and across the top. Even though it bakes, you can get ready any toppings you’d like to serve it with, these kinds of as cream cheese or butter, lox, thinly sliced tomatoes, cucumbers, onions, or capers.
To provide: Loosen the focaccia if it’s trapped in any spot and slide it into a cutting board. Minimize into 12 squares, using a sharp knife to get via the onions on leading without having pulling them off, and changing any that scatter. Eat appropriate absent.
Do in advance: Focaccia keeps at home temperature for 1 to 2 days. Reheat on a baking sheet at 350°F for 10 to 12 minutes.
Be aware: These are not caramelized onions we do not will need 60 to 90 minutes in excess of low heat with continual stirring. That is not how any ancestor of mine cooked onions. I’m intentionally applying a bigger heat for far more rapidly made flavor. If they’re not selecting up shade by 20 minutes, bump up the warmth marginally. If they are coloring way too speedy to make it to 20 to 25 minutes, lower the warmth. We want to halting shy of a darkish bronzed colour, as the onions will complete in the oven and we really don’t want them to burn up.