Wash and dry all produce. Trim and thinly slice scallions, separating whites from greens. Halve tomatoes. Mince cilantro. Zest and quarter lime (for 4 servings, zest 1 lime and quarter both). Mince chili.

Melt 1 TBSP butter in a small pot over medium-high heat. Add half the scallion whites and ¼ tsp turmeric (½ tsp for 4 servings; you’ll use more later); cook until fragrant, about 1 minute. Stir in rice, ¾ cup water (1½ cups for 4), stock concentrate, and a big pinch of salt. Bring to a boil; 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, in a medium bowl, combine tomatoes, cilantro, remaining scallion whites, and juice from half the lime (whole lime for 4 servings). Season with salt and pepper. If you like your salsa spicy, stir in chili to taste.

In a small bowl, combine sour cream, a big squeeze of lime juice, and as much lime zest as you like. Stir in water 1 tsp at a time until mixture reaches a drizzling consistency. Season with salt and pepper.

In a second small bowl, combine cumin and ¼ tsp turmeric (½ tsp for 4 servings). Pat barramundi dry with paper towels. Season all over with salt and pepper. Season flesh sides with spice mixture. Heat a large drizzle of oil in a large, preferably nonstick, pan over medium-high heat. Add barramundi skin sides down and cook until skin is crispy, 4-5 minutes. Flip and cook until barramundi is opaque and cooked through, 2-3 minutes more.

Fluff rice with a fork; stir in scallion greens and 1 TBSP butter (2 TBSP butter for 4 servings) and season with salt and pepper. Divide between plates. Top rice with barramundi; garnish with salsa fresca and crema. Serve with any remaining lime wedges on the side.