Adjust rack to top positions (top and middle positions for 4 servings) and preheat oven to 425 degrees.

Wash and dry produce. Halve cucumber lengthwise; thinly slice crosswise into half moons. Trim and thinly slice scallions, separating whites from greens. Trim green beans, if necessary.

In a small bowl, combine cucumber, vinegar, ½ tsp sugar (1 tsp for 4 servings), and a pinch of salt. Set aside to pickle.

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

Add rice, 1¼ cups water (2¼ cups for 4 servings), and a 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.

Line a baking sheet with foil and lightly oil. Pat salmon* dry with paper towels. Place skin-side down on one side of sheet, then brush with half the sweet soy glaze and sprinkle with a pinch of chili flakes. (For 4 servings, spread salmon out across entire sheet.)

Toss green beans on empty side of baking sheet with half the garlic powder, as many remaining chili flakes as you like, a drizzle of oil, salt, and pepper. (Use a second baking sheet for 4.)

Roast on top rack until salmon is partially cooked, 8 minutes, then remove from oven and brush with remaining sweet soy glaze. Return to oven and roast until glaze is tacky, salmon is cooked through, and green beans are tender, 2-4 minutes more. (For 4, roast green beans on top rack and salmon on middle rack). TIP: Salmon may be finished before green beans; remove salmon from sheet and roast beans for another 2-4 minutes, if needed.

While salmon roasts, in a second small bowl, combine mayonnaise, jam, Sriracha, remaining garlic powder, 1 tsp water (2 tsp for 4 servings), and a pinch of salt.

Fluff rice with a fork; stir in half the scallion greens and 1 TBSP butter (2 TBSP for 4 servings); season with salt and pepper.

Divide rice between bowls. Top with salmon, green beans, and cucumber (draining first). Drizzle salmon and green beans with sauce; sprinkle bowls with remaining scallion greens and as many sesame seeds as you like. Serve.