Method:

1. In a large bowl, whisk 1⁄4 teaspoon sugar and the yeast with 1⁄2 cup plus 2 tablespoons lukewarm water and let stand until foamy, about 10 minutes. Stir in the semolina flour, 1 tablespoon olive oil, and the 1⁄2 teaspoon salt until the dough comes together. Scrape the dough onto a lightly floured work surface and knead until smooth, about 8 minutes. Transfer the dough to a clean bowl, cover with plastic wrap, and let stand at room temperature until doubled in size, about 2 hours.

2. Meanwhile, pour the tomatoes and their juice into a blender and purée until smooth. In a small saucepan, warm the remaining 1 tablespoon olive oil over medium heat. Add the garlic and cook, stirring, until fragrant and beginning to brown, about 2 minutes. Pour the tomatoes into the saucepan along with the remaining 1 teaspoon sugar, bring to a simmer, and cook, stirring occasionally, until the sauce thickens slightly, about 10 minutes. Remove the sauce from the heat, stir in the basil, and season liberally with salt and pepper.

3. Heat the oven to 210°C. Line a 9-by-5-inch loaf pan with parchment paper. Scrape the dough onto a lightly floured work surface. Using a rolling pin, flatten the dough into a 1⁄16-inch-thick, 26-by-18-inch rectangle, and position the rectangle so that a long side is nearest to you. Spread half the tomato sauce over the middle three-fifths of the rectangle, then sprinkle the sauce with half of the caciocavallo slices. Fold the two plain sides of the dough over so their edges overlap in the middle of the rectangle by 2 inches.