Adjust rack to top position and preheat oven to 425 degrees. Wash and dry produce.

Trim, peel, and halve carrots lengthwise; slice into ½-inch-thick half moons. Halve, peel, and cut onion into ½-inch-thick wedges.

Toss carrots and onion on a baking sheet with a drizzle of oil, half the cumin (all for 4 servings), and a pinch of salt and pepper. Roast on the top rack until tender, 18-20 minutes.

While veggies roast, heat a drizzle of oil in a small pot over medium-high heat. Add couscous and half the garlic powder (all for 4 servings); cook, stirring frequently, until garlic powder is fragrant and couscous is lightly toasted, 1-2 minutes.

Stir in ¾ cup water (1¼ cups for 4 servings) and a big pinch of salt. Bring to a boil, then cover and reduce heat to low. Cook until couscous is tender, 6-8 minutes. Keep covered until ready to serve.

While couscous cooks, halve tomatoes and roughly chop pistachios.

In a large bowl, whisk half the vinegar, 2 TBSP olive oil, 1 tsp salt, and ½ tsp sugar until sugar is dissolved (all the vinegar, 4 TBSP olive oil, 2 tsp salt, and 1 tsp sugar for 4 servings). Add tomatoes and toss until thoroughly coated.

Pat salmon* dry with paper towels; season with salt and pepper. Heat a drizzle of oil in a large, preferably nonstick, pan over medium-high heat. Cook salmon (skin side down) until skin is crisp, 5-7 minutes, then flip and cook until cooked through, 1-2 minutes more. Turn off heat; transfer to a plate to rest. Wipe out pan. 

Once veggies are roasted and couscous is cooked, stir into bowl with marinated tomatoes; add spinach and toss until spinach is slightly wilted.

Divide spinach salad between bowls and top with feta and pistachios. Serve.

Top salad with whole salmon and garnish with feta and pistachios.