Combine yeast, sugar, and warm water in the bowl of an electric mixer fitted with the paddle attachment. Let the mixture stand until foamy, about 5 minutes.

Add 4 ½ tsp olive oil, then add the flour and 4 ½ tsp salt. Mix on medium-low speed until combined.

Switch to the dough hook and knead on medium speed until smooth and elastic, about 5–7 minutes.

Transfer the dough to a lightly oiled large bowl, cover loosely with plastic wrap, and let rise in a warm, draft-free place until doubled in size, about 2 hours.

Preheat the oven to 180°C. Generously oil a 30x40 cm baking sheet, spread the dough evenly to fill it, and press it gently into the corners. Press in the cherry tomatoes and sprinkle with rosemary. Cover lightly with oiled plastic wrap and let rest for 30 minutes.

Drizzle with the remaining olive oil and sprinkle with sea salt. Bake for 25 minutes, until golden brown.

Cool for 20 minutes before serving. If not consumed the same day, wrap in plastic wrap and foil. It freezes well for up to 1 month.