Rinse the dry lentils and jasmine rice thoroughly under cold water in a fine-mesh sieve until the water runs clear, then set aside.
Dice the chicken breast into uniform 1-inch cubes and season evenly with the sea salt and black pepper.
Heat the olive oil in a medium heavy-bottomed saucepan over medium heat.
Add the chicken cubes to the pan and sear for 3-4 minutes until golden brown on all sides, then remove the chicken and set it aside on a plate.
In the same pan, add the diced onion, carrots, and minced garlic, sautéing for 3 minutes until the vegetables are softened and fragrant.
Stir in the rinsed rice, lentils, and dried thyme, toasting the grains for about 1 minute to enhance their nutty flavor.
Pour in the chicken broth and bring the mixture to a rolling boil.
Reduce the heat to the lowest setting, cover with a tight-fitting lid, and simmer for 18-20 minutes until the liquid is fully absorbed and the lentils are tender.
Return the browned chicken to the pan, fluff the pilaf gently with a fork, and let it sit covered for 5 minutes off the heat to finish steaming before serving.