Steps

1. Peel the 100g of yam.
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2. Place the peeled yam in a thick plastic bag and mash it until it loses its shape using a rolling pin or similar tool. (This is the key!) By mashing in a bag instead of using a grater, you can make it easily without getting your hands dirty.
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3. Add 2 tbsp of milk and 1 tbsp of Shiro Dashi (White Soy Sauce Base) to the bag with the mashed yam and knead to mix.
   🕒 01:12
4. Cut the 40g of bacon block into 5mm cubes.
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5. Trim the tough ends off the 50g of shimeji mushrooms (1/4 bunch) and roughly chop them. (This is the key!) Chopping the shimeji mushrooms and bacon finely adds umami without compromising the gooey texture of the yam.
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6. Add the cut bacon to a frying pan and heat over medium heat, stir-frying. (This is the key!) Since the bacon will release its own oil, oil is generally not needed.
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7. Once the bacon starts releasing oil, add the chopped shimeji mushrooms and stir-fry until softened.
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8. When the ingredients are cooked through and softened, turn off the heat, cut off the corner of the bag with the yam sauce, and pour it into the frying pan.
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9. Heat the yam sauce over low heat, stirring constantly, and simmer until it thickens. (This is the key!) Using yam naturally creates a white sauce-like thickness without the need for flour or butter.
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10. Once the yam sauce has thickened, turn off the heat, and place the warm 2 bowls of cooked rice into a gratin dish.
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11. Generously pour the yam sauce over the rice.
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12. Sprinkle 40g of mixed cheese (20g per serving) over the yam sauce.
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13. After sprinkling the cheese, bake in a toaster, oven, or under a broiler until the cheese is golden brown and slightly charred. (This is the key!) The aroma of the browned cheese further enhances the flavor of the gratin.
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