Slow-Roasted Green Beans with Sage

1/2 lb         tender green beans, trimmed
1/2 bunch   spring onions, trimmed with green tops still attached, diced
6 large       garlic cloves, each cut lengthwise into 4 slices
1/4 C          olive oil
1 1/2 T        fresh sage leaves
                 kosher salt, to taste
                 freshly ground black pepper
Preheat oven to 375°. Combine ingredients in a large bowl, season with salt and pepper. Toss to evenly incorporate. Transfer beans to a large, rimmed baking sheet.
Roast beans, stirring every 10 minutes, until wilted, shrunken, and browned at edges, about 1 hour. (You may need to stir more often toward end for even browning.)