• 2 tablespoons olive oil
• 1 large yellow onion, diced
• 2 medium carrots, diced
• 2 celery ribs, diced
• 4 garlic cloves, minced
• 2 tablespoons tomato paste
• 1 teaspoon ground cumin
• 1 teaspoon dried thyme (or Italian seasoning)
• 1 teaspoon smoked paprika (optional)
• 1 bay leaf
• 1½ cups green or brown lentils, dry and well rinsed
• 1 (14.5-ounce) can diced tomatoes with juices
• 6 cups low-sodium vegetable or chicken broth
• 1 to 1¼ teaspoons kosher salt, plus more to taste
• ½ teaspoon black pepper
• 3 cups baby spinach or chopped kale (optional)
• 2 tablespoons lemon juice, plus additional juice to suit your taste
• 2 tablespoons freshly chopped parsley, for finishing the dish
• Add red pepper flakes, Parmesan, or olive oil on top, if desired.