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

Trim, peel, and cut carrots on a diagonal into ½-inch-thick pieces. Trim and thinly slice scallions, separating whites from greens. Strip 1 tsp thyme leaves (2 tsp for 4 servings) from stems; finely chop leaves. Zest and quarter lemon.

Toss carrots on a baking sheet with a drizzle of olive oil, salt, and pepper.

Roast on top rack until golden brown and tender, 20-25 minutes.

Meanwhile, heat a drizzle of oil in a small pot over medium-high heat. Add scallion whites; cook, stirring occasionally, until just softened, 1 minute.

Stir in rice, ¾ cup water (1½ cups for 4 servings), and a pinch of salt. Bring to a boil, then cover and reduce to a low simmer. Cook until rice is tender, 15-18 minutes.

Keep covered off heat until ready to serve.

While rice cooks, pat chicken* dry with paper towels and season all over with paprika, salt, and pepper.

Heat a drizzle of olive oil in a large pan over medium-high heat. Add chicken and cook until browned and cooked through, 3-5 minutes per side. TIP: If chicken is browning too quickly, reduce heat to medium.

Turn off heat; transfer to a plate. Wipe out pan.

Swap in salmon* for chicken; cook (skin sides down), until skin is crisp, 5-7 minutes, then flip and cook until cooked through, 1-2 minutes more.

Melt 1 TBSP butter in pan used for chicken over medium heat. Add chopped thyme; cook until fragrant, 30 seconds.

Stir in stock concentrate and ¼ cup water (⅓ cup for 4 servings). Bring to a simmer, then immediately turn off heat.

Stir in sour cream and a squeeze of lemon juice. Season with pepper.

Fluff rice with a fork; stir in lemon zest and pistachios. (TIP: For extra richness, stir in 1 TBSP butter; 2 TBSP for 4 servings.) Season with salt and pepper.

Divide rice, carrots, and chicken between plates. Top chicken with sauce and sprinkle with scallion greens. Serve with remaining lemon wedges on the side.

Top salmon with sauce and sprinkle with scallion greens.