Heat oven to 450 degrees. While the oven is heating, mince the shallot. Cut or tear mozzarella into roughly ½-inch pieces. Place tomatoes on a quarter sheet pan or baking dish large enough for them to spread out in a single layer. Drizzle with 1 tablespoon olive oil, season with salt and pepper and shake to coat.

Roast the tomatoes, gently shaking the pan halfway through, until they have blistered, burst and blackened in spots, about 20 minutes.

Meanwhile, heat the remaining 1 tablespoon olive oil in a large, high-sided sauté pan or Dutch oven over medium. Add the couscous and shallot, season with salt and pepper, and cook, stirring occasionally, until the couscous is lightly toasted and the shallot is softened, about 3 minutes.

Pour in the wine and simmer, stirring and scraping up any browned bits on the bottom of the pan with a wooden spoon, until the wine has almost completely evaporated, about 30 seconds.

Stir in 3 cups water, increase the heat to high, cover and bring to a simmer. Uncover and cook, stirring frequently so that the couscous doesn’t stick to the bottom of the pan. Decrease the heat as needed to maintain a simmer until almost all the liquid has been absorbed, the couscous is al dente and the mixture is creamy, 8 to 10 minutes.

Remove the pan from the heat. Scrape half of the roasted tomatoes into the risotto along with any juices from the sheet pan or baking dish. Add the pesto and stir to combine. Taste and season with salt as needed. Stir in the mozzarella. Serve garnished with the remaining tomatoes, a drizzle of pesto and fresh basil, if desired.