In a large pot or dutch oven cook bacon over medium heat until fat is rendered and bacon is cooked fully about 5 minutes. Remove bacon, put aside and save.
Add butter, onion, and carrot in bacon fat and simmer until the onion is translucent 3-4 minutes. Transfer to a blender.
Add tomatoes, nutmeg, lemon juice, and herbs, and blend until smooth.
Transfer back to pot and add stock, season with salt and pepper and simmer on low for at least 20 minutes.
Ladle into soup bowls and top with grated parmesan cheese