Using a mandoline or a sharp knife, thinly slice the potatoes into rounds. Try to make the potatoes as thin as possible, so they cook quickly.
4 Yukon gold potatoes
Arrange the potatoes into layers in a baking dish, or into individual ramekins if you are making individual sides. Do not pack the potatoes into the dish too tightly, as you want the sauce to seep into the layers.
Heat a medium-sized pot over medium heat. Add the butter to the heated pan, and let it melt. Once the butter has melted, sprinkle in the flour, and combine with a whisk. The mixture should form a paste. Let the butter and flour mixture cook for 1-2 minutes to get rid of the raw flour taste.
2 tablespoon Salted butter, 2 tablespoon All purpose flour
Slowly stream in the cream while whisking the mixture vigorously, to ensure there are no lumps of flour. Continue to whisk the mixture occasionally until it comes to a simmer, and the sauce has thickened.
2 cups Half and half cream
Once the sauce has thickened to the point that you can coat the back of a spoon and you can draw a line through the back of the spoon, turn the heat to low. Add in the cheeses in batches. Whisk to combine the cheese, and then add another batch until all the cheese is combined into the sauce. Stir in the seasonings and fire roasted chillies, and remove from the heat.
1 cup Cheddar cheese, 1 cup Monterey Jack cheese, ½ cup Fire roasted green chillies, 1 teaspoon Garlic powder, 2 teaspoon Cajun seasoning, 1 teaspoon Onion powder, 1 teaspoon Smoked paprika, Salt to taste
Pour the cheese sauce over the potatoes, or ladle into the individual ramekins if you are using them. Top with the reserved cheese. Cover the baking dish with foil.
Bake the potatoes for 25 minutes with the foil on, and for another 20 minutes with the foil off. If you are baking in smaller ramekins, bake for 15 minutes covered with foil, and another 15 minutes with the foil off.