If your salmon has skin, carefully shear it off with a sharp knife. Cut salmon into large chunks.
In the bowl of a food processor, combine salmon, shallots, garlic, harissa paste, lemon juice, egg, and panko. Pulse for 2-3 minutes until a chunky but cohesive batter forms. You do not want a puree. Pour into an airtight container and refrigerate about 30 minutes. If you're in a pinch, you can get away with a 15 minute chill time.
When ready to cook, coat a large skillet with olive or avocado oil and set over medium heat.
Form 4 patties out of the salmon batter, pressing firmly together. Place into the skillet with about 1-2 inches space in between. Cover and sear about 5 minutes on one side, carefully flip and sear uncovered an additional 4-5 minutes until crispy. Remove to a plate.
Make the whipped goat cheese. In a CLEAN food processor (for the love of God please clean the shit out of your food processor if you used it for the salmon), combine all ingredients for the goat cheese and puree until creamy, about 1-2 minutes.
Toast burger buns under the broiler until desired shade of brown. To assemble the burgers, spoon goat cheese on the bottom bun and top with arugula. Place one burger atop, then finish with sliced cucumber, fresh herbs, and any other desired toppings. Eat up!