Bring a large nonstick pot to medium-high heat. Add your onion, carrot, celery, garlic, and a splash of water to prevent sticking. Sauté for 2 minutes, adding more water to prevent sticking as needed.
Pour in veggie broth and water and bring the mixture to a boil.
Add sweet potatoes and apples to the pot. Cover and reduce heat to medium-low. Bring to a simmer and let simmer until potatoes and apples can be very easily pierced with a fork (usually about 15 minutes).
Add pumpkin purée, curry powder, and ginger to the pot. Mix to incorporate and allow to cook for 3-5 minutes.
Blend up your soup by either carefully transferring it to a high powered blender and blending (this likely will need to be done in a couple of batches), or by using an immersion blender. (Typically you will get smoother results by using a regular blender rather than an immersion blender).
(If using a regular blender, pour soup back into the pot and return to medium heat). Add coconut milk, salt, and maple. Stir to combine and allow the soup to warm through evenly (this should only take a minute or two). If desired, you may add an optional ½ - 1 cup of water to get a thinner consistency.
Serve and top with pumpkin seeds, cilantro, and/or a drizzle of coconut milk if desired. Enjoy!