Skillet Scalloped Potatoes

Bahan-bahan (4 porsi)

• 6 medium Yukon Gold potatoes, peeled and thinly sliced
• 3 tablespoons unsalted butter
• 3 tablespoons all purpose flour
• 1 1/2 cups milk
• 1 1/2 - 2 cups shredded Gruyere cheese
• 2 cloves garlic, minced
• 1 sprig thyme
• Salt and pepper, to taste