Season the salmon. Mix zaatar, garlic powder, smoked paprika, sumac, and salt in a small bowl. Put the salmon fillets in a Ziploc bag, then add 2 tsp olive oil and the entire spice mix. Seal the bag and shake until salmon is well coated. I also rub the salmon through the bag if it looks like some of it is less well-coated.
Cook the salmon. Heat 1 tbsp olive oil in a pan over medium-high heat until pan is hot and oil is shimmering. Add salmon fillets and cook for 5 minutes on one side. Don’t touch them! When the 5 minutes is up, flip them and cook another 2-3 minutes, or until the thickest part flakes easily with a fork.
Make couscous. Follow the package directions. I got the kind that cooks in five minutes, so I’d recommend that.
Garnish and serve. Divide the couscous into two bowls and swirl in a pat of butter each. Make a little impression in the middle of each couscous mound and nestle the fish into it. Sprinkle generously with parsley and feta and sprinkle on a little more of the spices, if you want to. Serve with lemon wedges to squeeze over the dish.