Preheat oven to 400 degrees.

In a large bowl, toss together the green beans, fish sauce, pepper and olive oil.

Line a baking sheet with foil. Pour the green bean mixture onto the baking sheet, spreading out the green beans into a single layer as best you can.

Slide the baking sheet into the oven and set the timer for 10 minutes. After 10 minutes, grab some tongs and open the oven. Carefully pull out the baking sheet and turn over the green beans with your tongs. Place the baking sheet back into the oven.

Set the timer for another 10-12 minutes and roast the green beans until they're slightly brown at the edges and a little wilted.

Toss with more fish sauce or lime/lemon and serve immediately.