Heat 2 tablespoons of olive oil in a large pot over medium heat. Add chopped onion and sauté until translucent, about 5-7 minutes. Then add minced garlic and grated ginger, cooking until fragrant, about 1-2 minutes.

Stir in ground cumin, ground coriander, and optional cayenne pepper. Cook for 30 seconds to bloom the spices.

Pour in 4 cups of vegetable broth followed by cubed sweet potatoes and chopped apple. Stir to combine.

Bring to a boil, then reduce heat to low and cover. Let simmer for 20-25 minutes until sweet potatoes are tender.

Use an immersion blender to puree the soup until smooth, or transfer it to a countertop blender in batches.

Stir in 1 cup of coconut milk until fully incorporated.

Season with salt and pepper to taste.

Warm the soup on low heat without boiling, stirring occasionally.

Ladle soup into bowls and garnish with optional toppings.