Peel the potato skin and dice to 4-5 mm. Soak in water for 5 minutes. Drain well, and sprinkle granulated sugar.
Peel the other potato and microwave (500-600W) for 3 minutes, then mash well.
Bring the cream cheese and butter to room temperature naturally, or microwave for 20 seconds to soften. Preheat the oven to 180℃.
Knead the cream cheese and butter together, add the granulated sugar and mix until it becomes light and fluffy.
Add the beaten egg, vanilla extract, step 2 potato, and skimmed milk in that order, mixing well with each addition.
Combine and sift in the cake flour and baking powder, and mix with a rubber spatula until it becomes smooth.
Pour the batter into your mold and top each muffin with the step 1 potato. Bake for 25 minutes at 180℃.
When they're done, cool, then remove from the molds.
Transfer to serving plates. Wrap and keep in the fridge if you are not eating immediately.
Story Behind this Recipe
I want to make many kinds of mild desserts using potatoes from Hokkaido.
This time, I used a silicon muffin mold. Depending on the mold you are using, you may have to coat it with oil and sprinkle flour in advance. Adjust the baking time according to your microwave and oven.