The Best Cheesy Scalloped Potatoes

• 4 tablespoons butter
• 1/2 cup chopped onion
• 1 teaspoon ground mustard
• 1 teaspoon salt
• 1/2 teaspoon coarsely ground pepper
• 2 garlic cloves, minced
• 1/4 cup all-purpose flour
• 2 cups whole milk
• 3 blocks (4 ounces each) sharp cheddar cheese, shredded and divided
• 1 block (4 ounces) Monterey Jack cheese, shredded
• 3 pounds russet potatoes, peeled and thinly sliced
• 3/4 cup dry bread crumbs
• Minced chives, optional

1. Preheat oven to 350u0b0. In a Dutch oven, melt butter over medium heat. Add onion, mustard, salt and pepper; cook until onion is tender, 6-8 minutes. Add garlic; cook until fragrant. Whisk in flour; continue whisking 3-5 minutes.
2. Whisk in milk; bring to a boil. Reduce heat; simmer, uncovered, until thickened slightly, 8-10 minutes. Gradually stir in 2 cups shredded cheddar cheese; stir in Monterey Jack cheese. Add potatoes and toss to coat. Simmer 10 minutes, stirring frequently.
3. Transfer potato mixture to a greased 13x9-in. baking dish. Top with remaining cheddar cheese. Bake, uncovered, for 1 hour. Top with bread crumbs; return to oven until potatoes are tender, 10-15 minutes. Let stand 15 minutes before serving. If desired, sprinkle with chives.

butter, onion, ground mustard, salt, ground pepper, garlic, allpurpose, milk, blocks, cheese, russet potatoes, bread crumbs, chives

Taken from www.tasteofhome.com/recipes/the-best-cheesy-scalloped-potatoes/ (may not work)