Dice mozzarella cheese into about 1 cm cubes and bacons into 1 cm squares.
Fry bacon in a frying pan until crispy (do not use oil).
Wash any dirt off the potato skins. Wrap individual potatoes in a plastic wrap and microwave until soft. (I microwave them for about 5 minutes, but it'll depend on the size of the potatoes.)
Once the potatoes are soft, peel them while they're hot. Remove any of the bigger eyes. Place in a bowl.
Mash potatoes with a masher or a fork. Combine with bacon, milk, salt and pepper and mix thoroughly. Set aside to cool.
When the potatoes in Step 2 is cooled enough so that you can hold them and scoop about 1 1/2 to 2 tablespoon in your hands. Bury about 2 cubes of cheese and form into round balls.
Repeat Step 6 and make 12 balls. (Make sure to fold in the cheese well so it won't stick out!)
Coat with flour, eggs, and panko in order. Deep-fry until golden brown.
Arrange on a plate and serve with ketchup if you'd like. Done.
You could make more and use them for bentos.
Cheese melting from freshly fried croquettes!! Also works well with the bacon!
Story Behind this Recipe
I came up with these croquettes when thinking of ways to eat mozzarella cheese. I love how the cheese melts when it's heated.
You can either boil or steam the potatoes. If microwaving, peeling will be difficult once cooled, so work while it's hot. Be careful not to burn yourself. When forming balls, make sure the cheese doesn't come out. If it sticks out, it will melt and dissolve when deep-fried.