Slow Cooker Scalloped Potatoes

INGREDIENTS

2 3/4 cups

peeled, 1/4-inch-sliced Yukon Gold potatoes (about 1 pound or 3-4 medium potatoes)*

2 3/4 cups

peeled, 1/6-inch-sliced sweet potatoes (about 3/4 pound or 2 medium/large potatoes—slice these slightly thinner than the Yukon Gold potatoes)*

Kosher salt (about 1 1/2 to 2 teaspoons, plus 1/4 to 1/2 teaspoon for the sauce)

Freshly ground black pepper (about 1 to 1 1/2 teaspoons for the potatoes, plus 1/8 to 1/4 teaspoon for the sauce)

4 tbsp

unsalted butter

1/4 cup

finely diced yellow onion (about 1/2 of a small onion)

1/4 cup

all-purpose flour

2 cloves

garlic, minced (about 1 teaspoon)

2 cups

nonfat milk

1/4

teaspoon freshly grated nutmeg*

1 cup

(about 2 1/2 ounces) freshly grated sharp cheddar cheese*

2 tsp

chopped fresh thyme

1/4 cup

freshly grated Parmesan cheese