Peel the onion and garlic clove and chop both finely. Score, core and finely chop the chilli pepper. Sauté the onions, garlic and chilli in 2 tablespoons of hot olive oil. Briefly sauté the tomato paste and sugar. Add the orange juice and zest and reduce a little. Add the peeled tomatoes, salt and vegetable stock, bring to the boil, cover and simmer over a medium heat for 20 minutes.
Cut the ciabatta lengthways into thin slices and place on a baking sheet. Roast under the hot grill on the second rack from above for 2-3 minutes until golden brown.
Spread the basil pesto on the bread strips.
Puree the soup finely. Season to taste with salt, sugar and pepper and serve drizzled with 2 tablespoons of olive oil. Serve with pesto bread.