To make ahead: Prepare through Step 1 and freeze for up to 6 months. Continue with recipe. Refrigerate soup for up to 4 days or freeze for up to 4 months. Reheat before serving.
To prepare freezer pack: Combine picked over and rinsed lentils, chopped onions, diced carrots, finely chopped garlic, coriander, bay leaves, cumin, oregano, pepper and cayenne in a sealable plastic bag. Seal and freeze for up to 6 months.
To prepare soup: Empty the freezer bag into a 6-quart slow-cooker. Add broth. Cover and cook on High for 4 hours or Low for 8 hours.
Discard bay leaves. Transfer half of the soup to a blender and puree. (Use caution when blending hot liquids.) Return the pureed soup to the slow cooker and stir in coarsely chopped spinach, tomatoes, coconut milk, chopped parsley, vinegar and salt; heat through.
Percentages are based on a diet of 2000 calories a day.