Chop bacon into small pieces.

Mince garlic.

Chop celery, onion, and carrot.

In a large soup pot, saute bacon over medium heat until browned and crispy (about 5 minutes).

Remove bacon with a slotted spoon and set aside on a plate lined with paper towels.

Add garlic, celery, onion, carrot, bay leaves, and thyme to the pot.

Saute until vegetables are softened (about 6 minutes).

Add lentils, chicken stock, and diced tomatoes with juice to the pot.

Bring to a boil.

Reduce heat and simmer until lentils are tender (about 45 minutes).

Thin with additional stock if needed and simmer for 5 minutes or until hot.

Discard bay leaves.

Season with salt and pepper to taste.

Ladle into heated bowls.

Garnish with reserved bacon.