Heat the butter in a large soup pan or Dutch oven over medium heat.
Add the bell pepper and onion then cook, stirring often, for 5-7 minutes, or until softened and the onion is becoming translucent.
Add the minced garlic and ginger and cook, stirring constantly, for 1 minute.
Add 1 teaspoon of lime juice, scraping up the bits on the bottom of the pan then add the red curry paste and chili garlic paste, cook for 2 minutes, stirring constantly.
Add the remaining lime juice, fish sauce, soy sauce, and chicken broth. Cook for 1 minutes, stirring frequently.
Add the coconut milk and whisk until well combined. Bring to a boil over medium high heat then reduce to a simmer.
Add the lemon grass pieces, cilantro stems, and mint sprig. Simmer for 10 minutes.
Remove the lemon grass pieces, cilantro stems, and mint sprig.
Add the rice noodles and cook for 6 minutes, stirring often.
Add the shrimp and cook for another 3-4 minutes, or until cooked through and the noodles are tender. Taste and season with sea salt and lime juice, to taste.
Ladle into bowls and serve with lots of freshly chopped cilantro on top and lime wedges, sriracha, and soy sauce on the side.
Serve immediately. Enjoy.