6 cups vegetable broth or reduced-sodium chicken broth
2 cups water
3 cups chopped cauliflower
1 3/4 cups lentils
1 28-ounce can diced tomatoes
2 tablespoons tomato paste
4 cups chopped fresh spinach or one 10-ounce package frozen chopped spinach, thawed
1/2 cup chopped fresh cilantro
2 tablespoons lemon juice
Combine onions, carrots, garlic, oil, cumin, coriander, turmeric, cinnamon and pepper in a 5- to 6-quart slow cooker. Add broth, water, cauliflower, lentils, tomatoes and tomato paste and stir until well combined.
Cover and cook until the lentils are tender, 4 to 5 hours on High or 8 to 10 hours on Low.
During the last 30 minutes of cooking, stir in spinach. Just before serving, stir in cilantro and lemon juice.
Make Ahead Tip: Stir in spinach (Step 3), cover and refrigerate for up to 3 days or freeze for up to 6 months. Stir in cilantro and lemon juice just before serving.