Wash and dry all produce. Adjust rack to upper position and preheat oven to 450 degrees. Trim, then thinly slice scallions, separating greens and whites. Drain pineapple in a strainer over a medium bowl, reserving juice. Roughly chop fruit. Trim any tough ends or strings from snap peas. Cut lime into quarters.

Heat a drizzle of oil in a large pan over medium-high heat. Pat chicken dry with a paper towel. Season with plenty of salt and pepper. Cook in pan skin-side down until browned, 4-5 minutes. Flip and cook on other side until browned, 3-4 minutes. Transfer to a foil-lined baking sheet, placing toward one side.

Roast chicken in oven until cooked through, about 20 minutes total. Meanwhile, heat a drizzle of oil in a small pot over medium-high heat. Add half the scallion whites and half the pineapple. Cook, tossing, until softened, 1-2 minutes. Pour in 1 cup water and a pinch of salt. Bring to a boil.

Once water boils, add rice, then cover, lower heat, and reduce to a gentle simmer. Cook until tender, 12-15 minutes. Place pan used for chicken over medium-high heat Add remaining scallion whites and pineapple. Cook until pineapple starts to brown, 2-4 minutes. To bowl with pineapple juice, add ketchup, soy sauce, 1 tsp sugar, a pinch of chipotle powder, and 2 TBSP water and stir to combine.

Add ketchup mixture to pan with pineapple. Simmer until slightly thickened, 2-4 minutes. Season with salt and pepper. (TIP: Add more chipotle for extra heat.) Remove pan from heat and stir in a big squeeze of lime. Once chicken has roasted 10 minutes, add snap peas to empty side of same baking sheet and toss with a drizzle of oil, salt, and pepper. Brush chicken with just enough sauce from pan to coat (keep the rest separate for adding at end).

Return sheet to oven and roast until snap peas are tender, 8-10 minutes. Fluff rice with a fork, then stir in 1 TBSP butter and a big squeeze of lime. Season with salt and pepper. Divide between plates and arrange chicken on top. Spoon over remaining sauce from pan. Serve snap peas to the side. Garnish with scallion greens.