Easy, Cheesy Potato Gratin

Ingredients

• 0.3 teaspoon pepper black freshly ground
• 1.5 tablespoons butter 
• 6 tablespoons flour all-purpose
• 1 tablespoon chives fresh chopped
• 1 tablespoon thyme leaves fresh chopped
• 4  garlic cloves minced
• 0.3 cup aged gruyère cheese shredded
• 3 cups milk 2% divided reduced-fat
• 0.3 cup parmigiano-reggiano cheese grated
• 40 ounce potatoes home-style (such as Simply Potatoes)
• 0.5 teaspoon salt 

Equipment

• sauce pan
• oven
• knife
• whisk
• plastic wrap
• baking pan
• broiler
• microwave

Directions

1. Preheat oven to 40
2. Arrange potatoes in a broiler-safe 11 x 7-inch baking dish coated with cooking spray. Cover with plastic wrap; vent. Microwave at HIGH 10 minutes; uncover carefully.
3. Melt butter in a medium saucepan over medium heat; swirl to coat.
4. Add thyme and garlic; saut 3 minutes.
5. Sprinkle with flour; stir in 1/3 cup milk. Cook 1 minute, stirring constantly with a whisk. Stir in remaining 2 2/3 cups milk. Bring mixture to a simmer; cook 4 minutes or until slightly thick, stirring frequently.
6. Remove from heat. Stir in salt, pepper, and Gruyre.
7. Pour sauce over potato mixture; sprinkle with Parmigiano-Reggiano.
8. Bake at 400 for 20 minutes or until potatoes are tender when pierced with a knife.
9. Turn on broiler (leave dish in oven). Broil gratin 2 minutes or until browned.
10. Sprinkle with chives.