01 - Dissolve the active dry yeast and sugar in lukewarm water in a small bowl. Let the mixture stand for 10 minutes until the surface becomes frothy and bubbly, confirming the yeast is alive and active.
02 - Combine the bread flour and salt in a large mixing bowl. Create a well in the center and pour in the activated yeast mixture along with the olive oil. Stir with a wooden spoon or your hands until a cohesive, sticky dough comes together.
03 - Turn the dough out onto a lightly floured work surface. Knead firmly for 8 to 10 minutes, pushing and folding, until the dough becomes smooth, springy, and passes the windowpane test when stretched thin.
04 - Transfer the dough to a bowl coated with olive oil, turning once to coat the surface. Cover tightly with a damp kitchen towel and set in a warm, draft-free spot for 1 hour, or until the dough has doubled in volume.
05 - Preheat the oven to 425°F. Generously grease a 12×16-inch rimmed baking sheet with olive oil, ensuring the entire surface and edges are well coated.
06 - Gently deflate the risen dough and transfer it to the prepared baking sheet. Using your fingertips, stretch and press the dough outward to fill the pan, creating deep dimples across the entire surface.
07 - Brush the dimpled dough generously with olive oil. Scatter the chopped rosemary and flaky sea salt evenly over the surface. Press olives or halved cherry tomatoes into the dough, if desired.
08 - Allow the topped dough to rest uncovered in a warm area for 20 to 30 minutes until it appears visibly puffy and has risen slightly.
09 - Bake on the center rack for 20 to 25 minutes until the top is deeply golden brown and the bottom sounds hollow when tapped. Cool on the pan for 5 minutes before slicing and serving.