Preheat oven to 425°F/220°C/Gas Mark 7. Wash and trim your green beans, and remove any stems or bad beans.
Place parchment on a sheet pan. Place green beans on top of parchment. Drizzle olive oil over this followed by minced garlic.
Toss all together and spread out in one layer avoiding over crowding.
Season with salt and pepper. Slice lemons, remove seeds and layer those on top. Squeeze juice from the ends of the lemon over areas that don’t have lemon slices over them.
Roast for 10-15 minutes. This can also be roasted/baked at 375°F/190°C/Gas Mark 5 for about 18 minutes if you already have another dish in the oven such as my lasagna, which bakes at the lower temperature.