Au Gratin Potatoes
- 3 pounds red potatoes, scrubbed
- 2 cloves garlic, peeled
- 1 small onion, peeled and halved
- 1/4 cup all-purpose flour
- 1 1/2 teaspoons salt
- 1 teaspoon dry mustard
- 1/4 teaspoon cayenne pepper
- 1/4 teaspoon freshly ground pepper
- 3 cups low-fat milk, divided
- 1 1/3 cups shredded sharp Cheddar cheese, divided
- 1/2 cup fine dry breadcrumbs
- 2 teaspoons extra-virgin olive oil
- Preheat oven to 350°F. Coat a 9-by-13-inch baking dish with cooking spray.
- Place potatoes in a large saucepan and cover with cold salted water. Bring to a boil, reduce heat to medium and cook, covered, until barely tender, 10 to 12 minutes. Drain, cool and slip off skins.
- Coarsely shred potatoes in a food processor or with the large-holed side of a four-sided grater. Set aside.
- Combine garlic, onion, flour, salt, mustard, cayenne and black pepper in a food processor; pulse until finely chopped. Add 1/2 cup milk and process until smooth. Scrape into a medium saucepan, add remaining 2 1/2 cups milk and bring to a simmer over medium heat, stirring constantly. Simmer, stirring, until thickened, about 5 minutes. Remove from heat and stir in 1 cup cheese until melted.
- Combine potatoes and the cheese mixture in a large bowl. Transfer to prepared baking dish.
- Combine remaining 1/3 cup cheese, breadcrumbs and oil in a small bowl. Season with salt and pepper and mix with your fingers. Sprinkle crumb mixture evenly over the potato mixture.
- Cover pan with foil and bake for 40 minutes. Uncover and bake until golden brown and bubbling, about 20 minutes more. Let stand for 10 minutes before serving.