2 tablespoons olive oil

1 large onion, diced

2 carrots, diced

2 celery stalks, diced

4 cloves garlic, minced

1 teaspoon ground cumin

1 teaspoon ground coriander

1 teaspoon smoked paprika

1/2 teaspoon dried thyme

1/4 teaspoon red pepper flakes (optional)

1 bay leaf

1 can (14.5 oz) diced tomatoes

1 1/2 cups dried green or brown lentils, rinsed and drained

6 cups vegetable broth

1 cup chopped kale or spinach

1 tablespoon lemon juice

Salt and pepper to taste

Fresh parsley for garnish (optional)