Hearty French Potato Casserole

From Cook’s Illustrated No. 115

Ingredients:

• 3 slices thick-cut bacon, cut into ½-inch pieces
• 1 large onion, halved and sliced thin
• 1 ¼ tsp salt
• ½ tsp pepper
• 2 tsp chopped fresh thyme
• 1 ¼ cups low-sodium chicken broth
• 1 ¼ cups beef broth
• 3 lbs Yukon Gold potatoes, peeled
• 2 Tbs unsalted butter, cut into 4 pieces

1. Adjust oven rack to lower-middle position and heat oven to 425 degrees. Grease 13 by 9-inch baking dish.

2. Cook bacon in medium saucepan over medium low heat until crisp, 10 to 13 minutes. Using slotted spoon, transfer bacon to paper towel-lined plate. Remove and discard all but 1 Tbs fat from pot.
3. Return pot to medium heat and add onion and ¼ tsp salt; cook, stirring frequently, until onion is soft and golden brown, about 25 minutes, adjusting heat and adding water 1 Tbs at a time if onion or bottom of pot becomes too dark. Transfer onion to large bowl; add bacon, thyme, remaining 1 tsp salt, and pepper.
4. Add broths to now-empty saucepan and bring to a simmer over medium high heat, scraping bottom of pan to loosen any browned bits.
5. Slice potatoes ⅛ inch thick. (Do not soak or rinse potatoes, this removes the starch which is needed in this recipe.) Transfer to bowl with onion mixture and toss to combine. Transfer to prepared baking dish. Firmly press down on mixture to compress into even layer. Carefully pour hot broth over top of potatoes. Dot surface evenly with butter.
6. Bake, uncovered, until potatoes are tender and golden brown on edges and most of liquid has been absorbed, 45 to 55 minutes. Transfer to wire rack and let stand for 20 minutes to fully absorb broth before serving.

Prep and Cook time: 2 hours 15 minutes