In a food processor or blender, combine pineapple juice, soy sauce, ketchup, brown sugar, fresh garlic, and canola oil. Blend until smooth to create the marinade.
Place chicken tenderloins and marinade in a zip-lock bag. Seal and mix well to coat all pieces evenly. Marinate in the refrigerator for at least 1 hour, or up to 24 hours for best flavor.
Grease a grill pan, cast iron grill, outdoor grill, or non-stick skillet.
Cook chicken, flipping halfway through, until the internal temperature at the thickest part reaches 165°F. Once fully cooked, immediately brush honey generously on both sides and remove from heat.
Slice fresh pineapple into ½–1 inch thick rings. Grill on both sides until caramelized with grill marks.