Pat the salmon dry and season lightly with salt, pepper, and a pinch of lemon zest. This helps build a tasty crust as it cooks.
In a large skillet, heat 1 tablespoon olive oil over medium-high. Place the salmon skin-side down (if using skin-on) and sear 3–4 minutes until the skin is crisp and the flesh is mostly opaque. Flip and cook 1–2 minutes more. Transfer salmon to a plate, leaving the flavorful bits in the pan.
Add the couscous (dry) to the pan and stir to toast for 1 minute. Sprinkle in the smoked paprika (if using) for color and aroma.
Pour in the broth, lemon zest, and lemon juice. Bring to a gentle simmer, then return the pan to a simmer. Stir once, then nestle the salmon back on top of the couscous. Scatter the halved tomatoes if using.
Cover the pan and cook 5–7 minutes, or until the couscous is tender and the salmon registers 145°F (63°C). If you’re using pearl couscous, it may take a minute or two longer.
If using spinach, stir it in now and cook just until wilted. Taste and adjust salt. Garnish with chopped parsley and extra lemon wedges.
Remove from heat and let rest for a minute. Fluff the couscous with a fork before serving so it stays light and fluffy.
