In a large bowl, combine warm water, instant yeast, and honey. Whisk gently and let sit for 5 minutes until foamy.

Add 1/4 cup olive oil and fine sea salt to the yeast mixture, whisking well. Gradually add the flour, mixing with a wooden spoon or a stand mixer with a dough hook until a shaggy dough forms. It will be sticky.

Knead the dough for 5-7 minutes until it becomes smooth and elastic, or cover the bowl and let it rest for 30 minutes, then perform 2-3 sets of stretch and folds over the next hour, resting 15-20 minutes between each set.

Lightly oil a clean bowl, transfer the dough to it, and turn to coat. Cover with plastic wrap and let rise in a warm place for 1 to 1.5 hours, or until doubled in size.

Generously oil a 9x13 inch baking pan (or a similar size). Gently transfer the risen dough into the prepared pan, being careful not to deflate it too much. Gently stretch and press the dough to fill the pan.

Drizzle the top of the dough with a tablespoon or two of olive oil. Using your fingertips, gently dimple the entire surface of the dough, creating small indentations. Sprinkle with chopped rosemary and flaky sea salt, if using.

Cover the pan loosely with plastic wrap or a clean kitchen towel and let the dough rise for another 20-30 minutes, or until visibly puffy.

Preheat your oven to 400°F (200°C) during the second rise.

Bake the focaccia for 20-25 minutes, or until deeply golden brown on top and cooked through. The internal temperature should be around 200°F (93°C).

Remove from the oven and immediately transfer the focaccia to a wire rack to cool slightly. Serve warm or at room temperature. Enjoy!