thickness as the potatoes so everything cooks evenly and softens at the same time.
In a small bowl, stir together the flour, salt, and pepper (if using). This simple mixture will lightly coat the layers and help turn the butter and onion juices into a silky, almost gravy-like coating as everything cooks.
Arrange a single, even layer of potato slices on the bottom of the slow cooker, overlapping slightly like shingles. Scatter a layer of onions over the potatoes. Sprinkle a teaspoon