Heat coconut oil in a large heavy-based pot over medium-high heat.

Add the diced onion and sauté for 3 to 4 minutes until translucent.

Stir in the garlic and ginger, cooking for 1 minute until fragrant.

Add the red curry paste and cook for 2 minutes, stirring constantly to caramelize the paste and release aromatics.

Add the pumpkin cubes and stir to coat thoroughly in the curry mixture for 2 minutes.

Pour in the vegetable broth and bring to a boil, then reduce heat to medium-low and simmer for 15 to 20 minutes until the pumpkin is fork-tender.

Remove from heat and use an immersion blender to process the soup until completely smooth and creamy.

Stir in the coconut milk (reserving 2 tablespoons for garnish), lime juice, fish sauce, and sugar.

Return to low heat for 2 minutes to warm through; do not boil.

Ladle into bowls and garnish with a drizzle of reserved coconut milk, fresh cilantro, and toasted pumpkin seeds.