Add the oil to a soup pot and bring the heat to medium.
Add the onion, carrots, celery, and garlic cloves and cook for 5 minutes stirring frequently.
Add the cumin, salt, smoked paprika, and thyme. Cook for one minute.
Add the split peas, broth, bay leaf, and potato. Bring it to a boil, then lower to a simmer, cover, and cook for 45 minutes until the peas have broken down.
Remove the bay leaf. Add the spinach and lemon juice and stir to wilt the spinach
Leave the soup as is, or blend about ⅓ of the soup with an immersion or stand up blender.