1
Adjust rack to top position and preheat oven to 425 degrees. Lightly oil a baking sheet. Wash and dry produce.
Finely chop parsley. Halve, peel, and finely chop shallot. Trim green beans if necessary. Quarter lemon.
Melt 1 TBSP plain butter (2 TBSP for 4 servings) in a medium pan over medium-high heat. Add panko and toast, stirring, until golden and fragrant, 2-3 minutes.
Turn off heat; transfer to a shallow dish and stir in garlic powder, half the parsley, and a pinch of salt and pepper. Wipe out pan.