Adjust rack to middle position (top and middle positions for 4 servings) and preheat oven to 425 degrees. Place 2 TBSP butter (3 TBSP for 4) in a small bowl and bring to room temperature.

Pat chicken* dry with paper towels and season all over with salt and pepper; place on one side of a baking sheet (spread out across entire sheet for 4).

Brush tops of chicken with ½ TBSP dressing each (save the rest for serving). Sprinkle with Monterey Jack. Crush crispy onions in their package, then sprinkle over cheese, pressing to adhere.

Roast on middle rack for 5 minutes (you’ll add more to the sheet then).

Meanwhile, wash and dry produce. Trim green beans if necessary.

Once chicken has roasted 5 minutes, remove sheet from oven. Carefully toss green beans on empty side with a drizzle of oil, salt, and pepper. (For 4 servings, leave chicken roasting; add green beans to a second baking sheet and roast on top rack.)

Return to middle rack until green beans are tender and chicken is browned and cooked through, 12-15 minutes more.

Meanwhile, combine softened butter with garlic powder to taste. Season with salt and pepper.

Halve and toast ciabatta. Spread cut sides with garlic butter. Cut each half on a diagonal.

Toss green beans with 1 TBSP plain butter (2 TBSP for 4 servings) until melted. Season with salt and pepper.

Divide chicken, green beans, and garlic bread between plates. Serve with remaining dressing on the side.