Vegetables:

• 2 tablespoons olive oil
• 1 medium yellow onion, chopped
• 2 carrots, peeled and diced
• 2 celery stalks, diced
• 3 cloves garlic, minced

Seasonings:

• 1 1/2 cups dried brown or green lentils, rinsed
• 1 teaspoon ground cumin
• 1/2 teaspoon smoked paprika
• 1/2 teaspoon dried thyme
• 1/4 teaspoon red pepper flakes (optional)
• 1 bay leaf

Liquid and Garnish:

• 6 cups vegetable broth
• 1 (14.5 oz) can diced tomatoes
• Salt and black pepper to taste
• 1 tablespoon lemon juice
• 2 cups chopped fresh spinach or kale (optional)
• Fresh parsley for garnish