Layer the frozen green beans on a half sheet pan and toss with the onions, some olive oil, salt, pepper, and garlic powder.
Cut up the 4 pieces of bacon into small chunks and layer on TOP of the green bean mixture.
Mix well and spread out evenly in the pan.
Roast at 425ºF for about 15-20 minutes until the bacon is crispy and the green beans are tender crisp.