Clean and wash the leek and cut into fine rings. Peel, wash and grate potatoes. Melt 1 tablespoon of fat. Steam leek and potatoes for about 5 minutes. Season with salt and pepper.
Deglaze with broth, boil for 15-20 minutes. Take out some leek rings and puree the soup with a chopping stick. Stir in cream and cream cheese, bring to the boil and season again.
Dice the toast and cut the bacon into small pieces. Wash thyme, dab dry and chop. Leave the bacon in a dry pan until crispy, set aside. Heat the remaining fat in the same pan.
Fry the toast cubes in it until golden brown. Sauté the thyme briefly. Warm the remaining leek rings in the soup. Serve sprinkled with thyme, croutons and bacon.