Prepare the Dough: In a big bowl, mix the warm water, sugar, and yeast. Let it sit for 5 minutes so the yeast can activate. Then add the flour, salt, and 2 tablespoons of olive oil, and stir until combined. Mix until the dough becomes sticky.
Light Kneading: Knead the dough by hand for around 5 minutes until it turns smooth. If it’s too sticky, sprinkle in a little more flour.
First Rise : Cover the bowl with a clean towel. Set it in a warm area and allow the dough to rise for 1 to 1.5 hours, or until it doubles in size.
Shape the Dough: Grease an 8x8-inch baking pan with olive oil. Gently spread the dough into the pan. Let it rest again for about 20 minutes.
Add Toppings and Dimple: Use your fingertips to press deep dimples across the dough. Drizzle 1 tablespoon of olive oil over the top, then sprinkle with sea salt and chopped rosemary.
Bake the Bread: Preheat your oven to 425°F (220°C). Bake the focaccia for 20 to 25 minutes, or until the top is golden and crisp.
Cool and Enjoy: Take the focaccia out of the oven and allow it to cool slightly before serving. Slice it up and serve warm or at room temperature.