Sauté Aromatics:In a large pot over medium heat, heat coconut oil. Add diced onion, garlic, and ginger. Cook, stirring frequently, until fragrant and onions are translucent, about 3–4 minutes.
Build Flavor Base:Add red bell pepper and cook for another 2 minutes until slightly tender. Stir in red curry paste, cooking for about 1 minute to release flavors.
Simmer Soup:Pour in coconut milk, broth, fish sauce, lime juice, and sugar. Stir well and bring to a gentle simmer.
Add Shrimp:Once simmering, add shrimp to the pot. Cook until shrimp turn pink and opaque, about 4–5 minutes. Season with salt and pepper to taste.
Garnish and Serve:Remove from heat and serve immediately garnished with fresh cilantro, lime wedges, and red pepper flakes for additional spice if desired.