Melt the butter in a pot over medium heat. Whisk in the flour. Cook for a minute or two, then slowly whisk in the milk, followed by the broth. Season with the salt and pepper and let it cook until it is starting to thicken.
Once thickened, remove the pot from the heat and stir in the sour cream and the roasted red peppers.
Spray the inside of a slow cooker with nonstick cooking spray. Spread half of the potatoes in the bottom of the slow cooker. Carefully spread half of the cream sauce over the potatoes, then sprinkle half of the cheese over the top. Repeat the layers with the remaining ingredients.
Cook on low for 5-6 hours, or high for 3 hours.
Serve hot.
Notes
Nutrition information provided as an estimate only. Various brands and products can change the counts. Any nutritional information should be used as a general guide.