Gather and prepare all ingredients.
Peel and devein shrimps. Cut into bite-size pieces.
Heat up ghee on a medium-high heat and fry onion until soft. Add ginger and garlic and sauté for 1 minute, stirring frequently, to prevent burning.
Smash or bruise lemongrass stalks with the chef's knife side until they flatten a little. Cut each stalk in half lengthwise. Add lemongrass, mushrooms, red curry paste, and tomatoes to the pot with onion and ginger. Cook for 10 minutes until mushrooms are soft. Add water to the pot and bring to a simmer.
Add chopped shrimps to the pot and stir. Season with salt and pepper. Cook until shrimps are cooked through, about 5 minutes.
Stir in coconut aminos, lime juice, and cilantro. Taste and season with more salt and pepper, if needed.
Take off the heat and remove lemongrass. Enjoy!