Heat the coconut milk and water and set aside.

Heat the sesame oil in a large saucepan over medium heat.
Sauté the onion until it starts to soften, about 4 minutes.
Add the rice and stir constantly for about 2 minutes.
Stirring, add a ladle of coconut milk and water mixture, and cook until the rice has absorbed all the liquid.
Add the fish sauce, lime zest and juice, salt, and red pepper flakes.
Continue to add the liquid, ladle by ladle, stirring gently and often, until most of the liquid is absorbed.

As soon as the rice is al dente, add the peas and shrimp.
Stir everything gently until it’s hot and the shrimp are pink, about 4 minutes.
Stir in the chopped cilantro. Taste and drizzle with more lime juice and fish sauce if needed. Season with salt if necessary.