Sauté Aromatics: Heat the vegetable oil in a large pot over medium heat. Add the onion, garlic, and ginger. Sauté for about 3 minutes until the onion softens and the mixture is fragrant.
Add Curry Paste and Build the Broth: Stir in the red curry paste and cook for another minute. Pour in the coconut milk, broth, fish sauce, lime juice, and sugar. Bring the mixture to a gentle simmer.
Cook the Vegetables: Add the sliced red bell pepper and simmer for about 5 minutes, until it begins to soften.
Add Shrimp and Spinach: Add the shrimp to the pot, cooking for about 5 minutes until they turn pink and are cooked through. Stir in the spinach just before serving.
Adjust and Serve: Taste and adjust seasoning with salt and pepper if needed. Garnish with fresh basil or cilantro and serve with lime wedges on the side.
