Heat oil in a large skillet over medium heat. Add onion and cook until soft, about 5 minutes.
Stir in garlic and ginger, cooking for another minute until fragrant.
Add curry powder, cumin, cinnamon, and cayenne. Toast spices for 30 seconds, stirring constantly.
Stir in pumpkin, coconut milk, and broth until smooth.
Add salt and sugar. Bring to a simmer and cook for 10 minutes, stirring occasionally.
Stir in lime juice. Taste and adjust seasoning if needed.
Serve hot over rice or with naan. Garnish with cilantro.