Adjust rack to top position and preheat oven to 425 degrees. Wash and dry all produce. Trim and thinly slice scallions, separating whites from greens. Heat a drizzle of oil in a small pot over mediumhigh heat. Add scallion whites; cook 30 seconds to 1 minute. Stir in rice and 3/4 cup water (11/2 cups for 4 servings). Bring to a boil, then cover and reduce heat to low. Cook until tender, 15-18 minutes.

Meanwhile, drain pineapple over a small bowl, reserving juice. Roughly chop fruit. Trim green beans. Zest and quarter lime (quarter both limes for 4 servings). In a separate small bowl, combine pineapple, scallion greens, lime zest to taste, juice from 1 lime wedge, and 2 TBSP pineapple juice (3 TBSP for 4). Season with salt and pepper.

Toss green beans on a baking sheet with a drizzle of oil, salt, and pepper. Roast on top rack until browned and tender, 12-15 minutes.

Pat fish dry with paper towels; season all over with salt and pepper. Season flesh side with Southwest Spice; rub to evenly coat.

Heat a large drizzle of oil in a large pan over medium-high heat. Add fish, skin sides down. Cook until skin is crispy, 4-5 minutes. (TIP: Lower heat if skin begins to brown too quickly.) Flip and cook until fish is opaque and cooked through, 2-3 minutes. Turn off heat; transfer to a paper-towel-lined plate.

Fluff rice with a fork; stir in 1 TBSP butter (2 TBSP for 4 servings), juice from 1 lime wedge and as much remaining lime zest as you like. Season with salt and pepper. Divide rice, fish, and green beans between plates. Top fish with salsa. Serve with remaining lime wedges on the side.