In a large pot, heat the coconut oil over medium heat. Add the diced onion and sauté for about 3-4 minutes until translucent.
Stir in the minced garlic and grated ginger, cooking for an additional 1-2 minutes until fragrant.
Add the red curry paste to the pot, stirring well to combine with the onion mixture. Cook for another minute.
Pour in the coconut milk and vegetable broth, stirring to combine. Bring the mixture to a gentle simmer.
Add the shrimp and sliced bell peppers to the pot. Cook for about 5-7 minutes, or until the shrimp are pink and cooked through.
Stir in the fresh spinach and lime juice, cooking for an additional 1-2 minutes until the spinach is wilted.
Season with salt and pepper to taste. Serve hot, garnished with fresh cilantro.