Preheat oven to 350˚ and line a rimmed sheet pan with parchment paper.
On the sheet pan, lay the green beans on the pan and drizzle with 2 tbsp of the olive oil. Toss with your hands and evenly spread beans out.
Slice the tomatoes in half and place in a bowl with the remaining tbsp of olive oil, tossing gently.
Place the tomato mixture on top of the green beans down the center of the pan.
Sprinkle entire pan with salt, black pepper, garlic powder and onion flakes.
Sprinkle the parmesan cheese over the tomato mixture. (omit for Paleo and Whole30)
Roast for 25 minutes or until the green beans are tender.
Before serving drizzle balsamic vinegar over top.
Enjoy!