Once the croutons are finished, leave the oven on and line a baking tray with parchment paper and arrange the tomatoes and bell peppers on the tray with 1 tablespoon olive oil, dried herbs, and a generous pinch of salt.
Combine using your hands to coat, and place in the hot oven for about 30 minutes, or until vegetables begin to blister. Remove from the oven and set aside.
When the vegetables are just about done roasting, heat a small saucepan over medium heat and add 1 tablespoon of olive oil. Once hot, add the onions, garlic, salt and, chili flakes. Cook for 5-7 minutes, or until onions begin to soften. Add the tomato paste and cook for a minute, until fragrant, stirring often. Remove from heat.
Transfer contents of the saucepan along with the roasted vegetables and vegetable broth into a high speed blender. Blend until smooth, taste and adjust seasonings as needed. You can add more broth for a thinner consistency if you wish.
Pour the soup into bowls, and top with croutons. Add any garnishes at this time, such has a drizzle of olive oil, chilli flakes, pepper and/or fresh herbs.