Add butter, garlic and onion to a large pot and cook for 5 minutes or until onion is cooked. Add tomato paste and cook for a further 2 minutes.
Add tomatoes, vegetable stock, sugar, smoked paprika, chili powder, bay leaf and thyme to the pot and stir to combine. Bring to the boil and then turn down the heat and simmer for about 30 minutes, uncovered until the soup starts to thicken slightly.
Remove from the heat, remove bay leaves and thyme and stir in the cream.
Using a stick mixer, or transfer to a blender and whizz up until the soup is smooth.
Add salt and pepper to taste, and serve immediately (with grilled cheese!)