Bring 1 ½ cups of water to a boil in a medium saucepan. Add basmati rice and cook according to package instructions, typically around 10-15 minutes, until fluffy and tender. Remove from heat, fluff with a fork, and set aside.

In a large stockpot or Dutch oven, melt 2 tablespoons of unsalted butter over medium-high heat. Season the medium shrimp with kosher salt and freshly ground black pepper, then add them to the pot. Cook for 2-3 minutes until the shrimp turn pink and opaque. Remove shrimp and set aside.

In the same pot, add the diced onion and red bell pepper, and sauté for about 3-4 minutes until they soften and become fragrant.

Stir in the red curry paste, minced garlic, and freshly grated ginger. Cook for an additional 2 minutes until everything is aromatic.

Pour in 1 can of coconut milk and 2 cups of vegetable stock. Season with more salt and pepper to taste, then bring the mixture to a boil. Reduce the heat and let it simmer for about 8-10 minutes until the soup slightly thickens.

Add the cooked rice, shrimp, freshly squeezed lime juice, and chopped fresh cilantro to the pot. Stir gently until combined, allowing the soup to heat through for about 2 more minutes. Serve immediately.