recipe for scalloped potatoes

#### Ingredients: - **4 cups thinly sliced potatoes** (about 4-5 medium potatoes) - **1 small onion** (finely chopped) - **2 cloves garlic** (minced) - **3 tablespoons butter** - **3 tablespoons all-purpose flour** - **2 cups milk** (whole milk preferred) - **1 cup grated cheddar cheese** - **1/2 teaspoon salt** - **1/4 teaspoon black pepper** - **1/4 teaspoon ground nutmeg** (optional) - **Fresh parsley** (chopped, for garnish, optional)