How to Make It
Preheat the oven to 425°. Set a large rimmed baking sheet on the lowest rack of the oven. In a large bowl, toss the potatoes with the shallots, garlic, rosemary sprigs, thyme, olive oil and butter. Season with salt and pepper.
Remove the hot baking sheet from the oven and scrape the potatoes onto it, spreading them in an even layer. Roast on the bottom rack for 40 to 45 minutes, turning occasionally, until the potatoes are golden and crisp. Transfer to a platter and serve.