Depending on how long your cod is, cut into filets that can fit on your grill tray. Place in a bowl and cover with the marinade and a tablespoon of avocado oil. Let sit for at least 10 minutes.
While the fish in marinating, cut your bell pepper, pineapple and onion into slices that can either fit on the grill pan or in your skillet. Place in a bowl and toss with a tablespoon of avocado oil and salt.
Preheat your grill on high heat. You want it to get up to 450.
Place fish on a grill pan and if it fits, your salsa.
Place on your grill and cook for 4 minutes. Flip and cook for another 4 or until fully cooked. The cod will fall apart when it's fully cooked and will be opaque. You want your salsa to be slightly charred. That's the best flavor.
Remove from the grill and put the salsa on top of your cod and serve.