Make dough: In a large bowl, mix flour, 1 teaspoon kosher salt and instant yeast. Add water and knead the dough with a spoon, rubber spatula or [I have this one], mix until the water is absorbed and a shaggy, sticky dough forms. Cover with a towel or plastic wrap and let rise at room temperature for 1 3/4 to 2 hours until doubled. Alternatively, you can keep it in the fridge for 8 to 10 hours or overnight.
Meanwhile, prepare your onions: Heat a large sauté pan on medium heat. When hot, add 2 tablespoons olive oil. When oil is hot, add onion and 1 teaspoon kosher salt. Cook onions, stirring every minute or so, until medium brown, almost caramel color, about 25 minutes. [See Note at end.] When you finish the roti, scrape the onions onto a plate to cool.
Finish the Focaccia: When the dough has doubled, line a 9×13 cake pan with parchment paper and sprinkle with 2 tablespoons olive oil. Don’t spoil your dough, just scrape it out onto oiled parchment. Drizzle another tablespoon of olive oil over the top of the dough and use your fingers to flatten the dough, flattening it. It’s okay if it doesn’t reach the edges. Let the dough rest at room temperature for 15 minutes and preheat your oven to 425°F. After 15 minutes, fold the dough only where needed and add a little more in the corners. Let rest for a final 15 minutes before sprinkling on top with the onions, poppy seeds, and a few pinches of salt.
Bake the Focaccia: Bake for 25 minutes, until deep golden brown on the edges and top. While it’s baking, you can prepare any toppings you’d like to serve with it, such as cream cheese or butter, lox, thinly sliced tomatoes, cucumbers, onions, or capers.
serve: Loosen the focaccia if it’s stuck in any places and slide it out to a cutting board. Cut into 12 sections, using a sharp knife without ripping the top off the onion, and replacing any scraps. Eat right away
Proceed: Focaccia keeps at room temperature for 1 to 2 days. Heat on a baking sheet at 350°F for 10 to 12 minutes.
Comment: These are not caramelized onions; We don’t need 60 to 90 minutes on low heat with constant stirring. None of my ancestors cooked onions like this. I’m intentionally using high heat for more quickly developed flavor. If they haven’t picked up color by 20 minutes, lower the heat a bit. If they are coloring too quickly, reduce the heat to 20 to 25 minutes. We want to avoid a deep bronze color, as the onions will end up in the oven and we don’t want them to burn.