In a large pot, heat olive oil over medium heat. Add diced onion and sauté for 5 minutes until translucent and fragrant. Stir in minced garlic and grated ginger for another minute.

Add ground cumin and ground coriander, stirring for 30 seconds until aromatic. Optionally add cayenne pepper for heat.

Pour in vegetable broth, scraping any browned bits from the pot. Add diced sweet potatoes and chopped apple, stir well and bring to a gentle boil.

Once boiling, reduce heat to low, cover, and simmer for 20-25 minutes until the sweet potatoes are fork-tender.

Remove from heat and blend until silky smooth using an immersion blender. If using a traditional blender, allow to cool slightly before blending in batches.

Return blended soup to the pot over low heat and stir in coconut milk. Warm gently while stirring frequently to combine flavors.

Taste, adjust seasonings with salt and pepper, and warm through for another 5 minutes.

Ladle soup into bowls and garnish with optional toppings. Serve immediately and enjoy!