1. Preheat oven to 450 degrees. Line baking sheet with parchment paper.
2. Pat fillets dry with a paper towel and season with salt & pepper. In small bowl, combine pecans, garlic, and oil, and mix well. In a separate bowl, blend the mayonnaise, lemon pepper seasoning, and dill.
3. Place halibut fillets on prepared baking sheet. Spoon the mayonnaise mixture over each fillet, then sprinkle with the pecan mixture, and lightly press down using the back of a spoon.
4. Bake for 15 minutes, or until opaque and hot in center. Broil for 1 minute to brown topping.
Enjoy!