Preheat your grill to medium-high heat.
Lightly brush the pineapple rounds and habaneros with neutral oil to prevent sticking. Grill both for about 3–5 minutes on each side, until the pineapple is caramelized and has grill marks, and the habaneros are softened and slightly charred.
Once grilled, chop the pineapple into small pieces. Finely chop the habaneros, removing the seeds for less heat if desired.
In a mixing bowl, combine the chopped pineapple, habaneros, tomatoes, onion, and cilantro. Add the lime zest and juice, and season with salt to taste.
Stir well to combine. Let the salsa rest for about 15 minutes before serving to allow the flavors to meld.