Preheat the oven to 180°C Fan.
Wash tomatoes, remove any green stalks and cut them in half.
Place the tomatoes cut-side up on a large baking tray and scatter the peeled garlic cloves amongst the tomatoes.
Drizzle 1 tablespoon olive oil over the tomatoes and garlic. Grate some salt and black pepper over then scatter the dried thyme and dried oregano.
Roast for 35–45 minutes, until the tomatoes are soft and beginning to caramelise around the edges.
Whilst the tomatoes are roasting, heat the remaining 1 tablespoon of olive oil in a large saucepan over a medium heat. Add the chopped onion and cook for 5–7 minutes, stirring occasionally, until softened.
Stir the smoked paprika and ground cumin into the softened onion and cook for 1 minute.
Scrape the roasted tomatoes, garlic and all the juices from the roasting tray into the saucepan with the onion then add the stock, chopped basil and chopped tomatoes. Stir well.
Bring the soup to a boil, then reduce to a simmer for 15–20 minutes, stirring occasionally.
Remove soup from heat and using a stick blender or food processor blend the soup until smooth.
Return to pan and season to taste with the salt and pepper and if required stir in the optional teaspoon of sugar.
Serve in bowls and garnish with freshly chopped basil.