Preheat the oven to 350° F.
Place the salmon on a sheet pan, skin side down. Brush with olive oil and sprinkle with salt and pepper. Roast for 15 to 20 minutes, until just cooked.
Remove from the oven and cover tightly with aluminum foil. Allow to rest for 10 minutes and refrigerate until cold.
Meanwhile, place 2 Tbsp of the butter, 2 Tbsp olive oil, the onion, celery, red and yellow bell peppers, parsley, capers, hot sauce, Worcestershire sauce, crab boil seasoning, ½ tsp salt, and ½ tsp pepper in a large saute pan over medium-low heat and cook until the vegetables are soft (~ 15 to 20 minutes)
Cool to room temperature.
Flake the chilled salmon into a large bowl, and put about a quarter of it into the container of a food processor, along with the mustard
Turn the machine on, and let it run, stopping to scrape down the sides if necessary, until the mix becomes pasty.
Add the processed salmon back into the bowl with the rest of the flaked salmon
Add the bread crumbs, mayonnaise, and eggs. Add the vegetable mixture and mix well.
Cover and chill in the refrigerator for 30 minutes. Shape into 10 (2 ½ to 3-ounce) cakes.
Heat the remaining 2 tablespoons butter and 2 tablespoons olive oil in a large saute pan over medium heat.
In batches, add the salmon cakes and fry for 3 to 4 minutes on each side, until browned.
Drain on paper towels; keep them warm in a preheated 250° F oven and serve hot.
Serve with Herbed Lemon Yogurt Sauce
Herbed Lemon Yogurt Sauce
In a small bowl add the Greek yogurt, lemon juice, horseradish, and 2 ½ teaspoons thyme in a small bowl.
Season sauce to taste with salt and pepper
Mix until well combined