Grill pineapple. Heat grill to medium or a grill pan to medium-high. Once hot, place pinapple half on the grill and let cook, undisturbed, until it is charred on one side. Flip and continue to cook until all sides have grill marks, about 15 minutes. Let cool.

Combine. Once pineapple is cool, remove core and chop into small dice. Add minced red onion, chiles, and cilantro. Squeeze one lime half over the salsa and season with salt. Stir and taste. Add more lime juice or salt if needed.

Serve or store. Serve immediatley or keep in the refrigerator for up to 5 days.