Wash and dry all produce. Trim, then thinly slice scallions, keeping greens and whites separate. Pick and finely chop enough rosemary leaves from stems to give you 1 tsp. Halve, core, and dice apple.

Heat 1 TBSP olive oil in a small pot over medium-high heat. Add scallion whites and ½ tsp chopped rosemary. Cook until fragrant, about 30 seconds. Pour in ¾ cup water. Bring to a boil, then immediately stir in couscous and a large pinch of salt and pepper. Remove from heat, cover, and let stand until tender, about 10 minutes.

Meanwhile, pat pork dry with a paper towel. Season generously all over with salt and pepper. Melt 1 TBSP butter in a large pan over high heat. Add pork and cook until browned and cooked through, about 2 minutes per side. Remove from pan and set aside on a plate.

Reduce heat under pan to medium. Stir in remaining chopped rosemary, 1 TBSP vinegar (we'll use more later), maple syrup, stock concentrate, and ¼ cup water. Let simmer until thickened, about 1 minute. Stir in 1 TBSP butter, then season with salt and pepper. Return pork to pan, tossing to coat in sauce, then remove pan from heat.