1. Cut lemon in half. Squeeze juice from lemon into a 3-qt. saucepan. Add lemon halves, 2 Tbsp. salt, and 6 cups water, and bring to a boil over medium-high heat. Add salmon fillet (cut into 2 pieces, if necessary); cover and reduce heat to low. Simmer 4 minutes. (Center of salmon will be raw.) Carefully transfer salmon to a large bowl, and cool completely (about 10 minutes). Remove and discard skin, and flake salmon.
2. Preheat oven to 425°. Stir 1/2 cup panko and next 11 ingredients into flaked salmon.
3. Stir together melted butter and remaining 2 cups panko. Spoon 1 tsp. panko mixture into each cup of a lightly greased 24-cup miniature muffin pan. Add 1 Tbsp. salmon mixture to each muffin cup. Top each with 1 tsp. panko mixture.
4. Bake, in batches, at 425° for 10 minutes or until topping is golden brown. Serve warm with Ginger Rémoulade.