Heat olive oil in a large pot over medium heat.

Add onion, carrots, and celery, cooking until vegetables are softened, about 5 minutes.

Add minced garlic, cumin, and turmeric, cooking for another minute until fragrant.

Add lentils and vegetable broth to the pot. Season with salt and pepper.

Bring the soup to a boil, then reduce heat to low and simmer, covered, until lentils are tender, about 25-30 minutes.

In the last 5 minutes of cooking, add the chopped spinach or kale to the pot and stir until wilted.

Taste the soup and adjust seasoning if necessary.

Serve hot, with a side of whole grain bread.