Rinse lentils and pick out any hard or discolored ones and discard. Let rinsed lentils sit.
Add oil to a large pot and warm over medium heat. Add onion and cook for 4-5 minutes until onion starts to soften. Add garlic, carrots, cumin, turmeric, curry powder, herbs de provence, salt, pepper, and cayenne and stir another minute until spices are aromatic and well mixed in.
Pour in diced tomatoes, vegetable broth and lentils. Increase heat to high and bring to a boil. Reduce heat, partially cover, and let simmer for 30 - 35 minutes until lentils are cooked through but still holding shape.
Add coconut milk and stir to mix in.
Use a stick blender to blend a small amount of the soup to thicken. If you do not have a stick blender, remove 2-3 cups of the soup and place in a blender, blend, and then pour back into pot.
Add kale and and apple cider vinegar and cook for about 4-5 minutes longer until greens are soft.
Season with additional salt and pepper if desired. Ladle into bowls and top with sliced avocado to garnish if desired.
Soup will keep in the refrigerator for 4-5 days and freezes well in airtight containers for up to three months.