For the sauce: Combine all ingredients in a small bowl, season with salt and pepper and refrigerate at least 30 minutes.
For the salmon: Place salmon in a small saucepan. Cover with water and add the remaining ingredients. Bring to a simmer and cook for 8 to 10 minutes, until just cooked through. Let cool and flake with a fork.
For the griddle cakes: Place flaked salmon and crab in a medium bowl. Add mayonnaise, mustard, horseradish, red onions, garlic and mix until combined. Fold in egg whites then remaining ingredients and season with salt and pepper Heat 2 tablespoons of canola oil in a large saute pan. Add 1/4 cup of batter for each cake and flatten slightly. Saute on each side for 2 to 3 minutes or until golden brown. Top each pancake with a few slices of smoked salmon and drizzle with Roasted Garlic-Buttermilk Sauce. Garnish with chives and cilantro and finely chopped red pepper.