Peel the potatoes and slice them into 2 mm thick slices (you can slice the potatoes with the peeler too). Preheat the oven (a toaster oven is OK too).
Add the potatoes to a microwaveable dish and cover them with water. Wrap the dish with plastic wrap and microwave it for about 5 minutes.
Open the plastic wrap a little and drain the water. (The dish is very hot. Use oven mitts or a towel to handle it.)
While the potato is in the microwave, melt the butter (or margarine) in a skillet over low heat. Add the flour and sauté it.
Pour in the milk (or soy milk) and soup stock cube. Dissolve the soup stock and season the mixture with salt and pepper.
Once the sauce is well mixed, check the taste and adjust it with salt. If you're satisfied with the taste of the white sauce, add the potatoes and coat them with the sauce.
Mix them in evenly and turn off the heat.
Transfer the ingredients into a gratin (casserole) dish and top it with the grated cheese. Bake the gratin in a 200℃ oven for about 10 minutes. If you're using a toaster oven, bake until golden brown.
Garnish it with some parsley if you like and enjoy.
Story Behind this Recipe
I like potato gratin, but I think it takes a long time to cook the potatoes thoroughly. If you slice the potatoes and microwave them for 5 minutes they are ready to be used! By coating the potatoes with sauce instead of pouring the sauce on top, the entire dish becomes delicious. It was a big hit at a wine-tasting gathering.
I made a very simple potato-only gratin this time, but it also tastes delicious with some bacon and mushrooms too! This recipe reduces the cooking time by slicing the potato thinly and using a microwave.
You are only browning the top of the gratin in the oven or the toaster oven. So feel free to brown it to how you like, rather than sticking to the time that I wrote.