Peel and wash the carrots. Peel onions. Clean and wash the peppers. Cut everything into 1-2 cm pieces.
Heat the oil in a pot. Stir-fry the carrots, peppers and onions for about 2 minutes. Stir in curry paste. Sprinkle with sugar and deglaze with 2 tbsp. lemon juice. Approx. 3⁄4 Add l hot water. Stir in broth. Cover and cook for 15-20 minutes.
Finely puree the carrots with the hand blender, mixing in approx. 300 ml of hot water until the desired consistency is achieved. Bring the soup to the boil briefly. Season to taste with soy sauce and lemon juice. Serve as desired with Thai carrots and coriander pesto.