Step 1

Preheat oven at 180 C/ 350 F.

Step 2

Quarter both the roma and heirloom tomatoes. Cut the onions and carrots into big chunks.

Step 3

Place the tomatoes, carrots, onions and garlic on a baking tray, drizzle with olive oil and sprinkle half teaspoon salt on top. Give everything a good toss and place in the oven to bake for an hour. Alternatively you can also grill all the vegetables on a grill pan on the stove with a drizzle of olive oil and a sprinkling of salt.

Step 4

Transfer the grilled vegetables with their juices into a blender. Add a cup of stock and blend till smooth.

Step 5

Transfer to a pot with the remaining stock and cook over medium heat for 5-7 minutes. Add sugar, balsamic vinegar and chilli flakes and bring it to a quick boil.

Step 6

Finish with 2-3 tablespoons of the basil pesto.

Step 7

Taste the soup for seasoning and add more pesto and salt or pepper as required. Serve hot with grilled cheese, croutons or crackers.