Cut salmon into roughly equal-size pieces, each about 1 inch wide, 3 inches long and the thickness of the fillet. Refrigerate. (Note: To fry pieces that look like fish sticks, slice the salmon lengthwise so that the larger side of the fillet has a fairly uniform thickness. Bread all pieces as instructed, but cook the thinner pieces together and the stick-sized pieces together. Give each diner some stick-sized pieces and some smaller pieces.)
Mix flour, garlic powder and white pepper together in a pie plate or shallow pan. Combine milk and mayonnaise in another pie plate or shallow pan, mixing well with a fork or whisking to break up any lumps. Put bread crumbs and dill into a third pan.
Take a piece of fish and gently coat it in the flour, then carefully shake off any excess. Dip in milk mixture and drain off any excess, then coat with seasoned bread crumbs. Place the breaded fish onto a tray. Repeat with the remaining pieces of fish. Discard any excess liquid, flour mixture or breading mixture.
Pour 1 1/2 inches of vegetable oil into a large skillet. Heat over medium to medium-high heat until hot but not smoking. (Drops of water added to the skillet will sizzle.) Add 6 to 8 pieces of breaded fish (the fish cooks quickly and you must turn it, so don't try to do too many pieces at once). Fry until golden brown, turning to ensure even cooking, 2 to 3 minutes total for pieces about 1/2 inch thick. Remove with a slotted spatula and drain on paper towels.
Serve with Tartar Sauce or Lemon Aioli.
To Make Lemon Aioli: Place lemon juice, garlic and turmeric in a blender; process until smooth.
Pour into a small pan and bring to a simmer over medium-high heat. Reduce heat and simmer until about 2 tablespoons of liquid remain. Remove from heat, pour into a medium bowl and let cool.
Add mayonnaise, dill and salt and pepper to taste. Whisk until smooth. Cover and refrigerate at least 1 hour before serving.