Preheat oven to 400ºF; line a baking sheet with parchment. Prick sweet potatoes all over with a fork. Place on baking sheet and roast until potatoes are very tender and you can easily pierce with a knife, 45 to 60 minutes. Let cool. When cool enough to handle, cut in half and scoop out flesh; discard the skins.
Warm oil in a large saucepan over medium heat. Add onion, sprinkle with salt and cook, stirring occasionally, until very tender, about 6 to 7 minutes. Add garlic, ginger, and cayenne; sauté until fragrant, 1 to 2 minutes.
Add roasted potato to pan, then add coconut milk and broth, stirring to break up the potato. Bring to a boil, then reduce heat. Partially cover and simmer for 10 minutes.
Remove from heat; let cool slightly. Whisk in miso and Spore Probiotic Powder. Blend with an immersion blender until smooth (alternatively, transfer to a high-speed blender to blend). Taste and season with salt and pepper. Ladle into bowls, drizzle with yogurt and/or oil, sprinkle with paprika, if desired, and serve.