Soak the applewood chips in water for 30 minutes. Meanwhile, cook the quinoa as the label directs.
Drain the applewood chips and scatter them in a foil-lined flameproof roasting pan. Place the pan over two burners and heat over medium-low heat until the wood chips smoke, about 10 minutes. Place the salmon skin-side down on a wire rack and carefully set the rack over the wood chips. Cover the roasting pan tightly with foil and cook over medium-low heat until the salmon is just cooked through, 15 to 20 minutes. Remove the salmon from the smoker and let it cool to room temperature.
Preheat the oven to 350 degrees F. Remove and discard the salmon skin, then flake the salmon with a fork and transfer to a large bowl. Add the quinoa, egg, scallions, flour, lemon zest, Urfa pepper and 1 teaspoon salt. Mix until well combined. Form the mixture into 6 patties, about 1 inch thick and 2 1/2 inches wide.
Heat the coconut oil in a large cast-iron pan over medium-high heat. Sear the patties until crispy and deep golden brown, about 2 minutes per side. Transfer the patties to a rack set on a baking sheet and bake until cooked through, about 12 minutes. Serve the croquettes with lemon wedges.
Damaris uses Turkish Urfa pepper flakes to give these croquettes extra smoky flavor. Look for it online, or just use black pepper.