Peel and finely dice the onion and garlic. Peel and chop the potatoes and carrots. Heat the fat in a saucepan and fry the onion and garlic. Add potatoes and carrots and steam for about 4 minutes while stirring.
Wash the thyme, dab dry and add. Deglaze with broth, bring to the boil, cover and cook over medium heat for about 15 minutes. Take out about 4 tablespoons of vegetable cubes with a skimmer and put aside.
Remove thyme. Finely puree the soup, season with salt and pepper. Add 110 g crème fraîche. Arrange soup in bowls. Put 1 blob (10 g each) of crème fraiche in each bowl. Spread vegetable cubes on top and sprinkle with pepper.
Serve garnished with thyme leaves.