Blend the soaked cashews with ½ cup water until very smooth and set aside.
In the slow cooker, on a high setting, combine the onions, garlic, carrots, thyme, and bay leaves. Stir to mix. Add some salt and ground black pepper. Cover the crock-pot and let the onions cook for 10 minutes.
Add the potatoes, frozen black eyed peas and curry powder to the crock-pot. If you are using canned or cooked black-eyed peas, DO NOT add at this point. You will add them later in the process.*
Add 3 cups of very hot water or vegetable stock to the cooker. Stir to mix everything, then cover the crockpot and let it all cook for the next two hours or until the veggies and black-eyed peas are really tender.
Add the mushrooms and let the chowder cook for another 20 minutes.
Add the cashew cream and stir to mix.** Allow the chowder to warm through and add more salt and pepper as required. Garnish with scallions before serving.
*If you are using canned or cooked black-eyed peas, add them about an hour into the cooking time, when the veggies are nearly tender.
**If you don't plan to use the cashew cream, remove a few ladles of the chowder before you add the mushrooms and blend into a puree. Add the puree back to the crockpot. Add the mushrooms, cover, and cook for 20 more minutes.