In a small bowl, whisk together the olive oil, jerk seasoning, sea salt, and black pepper to create a marinade.
Rub the spice mixture evenly over the chicken breast until it is fully coated on all sides.
Heat a grill pan or outdoor grill over medium-high heat and cook the chicken for 6-7 minutes per side, or until the internal temperature reaches 165°F.
While the chicken is cooking, finely dice the pineapple, red onion, and red bell pepper.
Toss the diced fruit and vegetables in a bowl with the lime juice and chopped cilantro to assemble the salsa.
Warm the pre-cooked brown rice and place it at the base of a shallow bowl.
Allow the chicken to rest for 3 minutes, then slice it into strips and arrange them over the rice.
Top the chicken with a generous portion of the fresh pineapple salsa and serve immediately.