In a glass jar, whisk together the soy sauce, pineapple juice, brown sugar, ketchup, shallots, garlic, ginger, and a pinch of chili flakes. Pour 1/3 of the sauce over the chicken and let sit 15 minutes or up to overnight in the fridge.
Coconut Rice: Combine 1 (14 ounce) can coconut milk and 1/2 cup water in a medium pot. Bring to a low boil. Add 1 cup basmati rice and a pinch of salt. Stir to combine, cover, then turn the heat down to the lowest setting possible. Allow the rice to cook 10 minutes on low, then turn the heat off completely and let the rice sit, covered for another 15-20 minutes (don't take any peeks inside!). Remove the lid and fluff the rice with a fork.
Meanwhile, make the salsa: combine all ingredients in bowl. (Optionally, skip salsa and serve pineapple on the side.)
Heat the oil in a large skillet over medium-high heat. Add the chicken, cook 5 minutes until cooked through on both sides. Reduce the heat to medium and pour in the remaining soy sauce mix. Cook until the sauce glazes the chicken and begins to caramelize, about 5 minutes. Remove from the heat and stir in the cilantro.
Serve the chicken over rice and spoon the salsa over the chicken. Sprinkle on the diced avocado and a squeeze of lime.