Wash and trim green beans. Peel and cut carrots into ¼-inch thick strips that are 3-4 inches long (they should roughly match the size of the green beans so they cook at the same rate).
Whisk together olive oil, lemon juice, salt, pepper, parsley and thyme. Pour over the vegetables and toss well to coat.
Spread vegetables into an even layer on a rimmed baking sheet.
Roast for 25-30 minutes, stirring 2-3 times while roasting, until carrots are fork tender.