Korokke (Potato & Meat Croquette)

1. Gather all the ingredients.

To Prepare the Korokke Mixture

1. Peel and cut 2 lb russet potatoes into quarters. To a large pot, add the potatoes and enough water to cover. Bring it to a boil. Cook the potatoes until a skewer pierces the potato easily, about 15–20 minutes. Remove the pot from the heat and drain the water completely. When you do so, use the lid to hold back the potatoes so they don’t fall out of the pot.
2. Move the pot back to the stove. On low heat, shake the pot so that the remaining moisture will completely evaporate (but don’t burn them).
3. Turn off the heat and mash the potatoes, leaving some small chunks for texture. Set aside.
4. Meanwhile, finely chop 1 onion and ½ carrot. Remove the stems from 2 shiitake mushrooms and finely chop the caps.
5. Heat a large skillet on medium-high heat. Then, add 2 Tbsp neutral oil. Add the onion and sauté until soft.
6. Add the carrot and shiitake mushrooms and cook until soft.
7. Add 1 lb ground beef and break it up with a wooden spoon. When the meat is cooked through, add 1 tsp Diamond Crystal kosher salt, ¼ tsp white pepper powder, and freshly ground black pepper (to taste). Remove from the heat.
8. Drain the meat and add it to the pot with the mashed potatoes. Tip: Leave the cooking liquid behind as we don‘t want to introduce more moisture.
9. Crack and add 1 large egg (50 g each w/o shell) to the mixture.
10. Mix it all together until everything is well combined.

To Shape the Patties

1. While the mixture is still warm but not hot, form the Korokke patties into an oval shape. Place on a plate or tray and cover, then cool and rest the patties in the refrigerator for 15–30 minutes. (Do not skip!) TIP: Cooling prevents the croquettes from exploding while deep-frying. If you place warm patties in the hot oil, the internal temperature of the korokke will increase fast, causing them to release steam and explode through the breading. Resting the patties also helps the ingredients meld together.

To Bread the Korokke

1. Meanwhile, prepare ½ cup all-purpose flour (plain flour), 3 large eggs (50 g each w/o shell) (beaten), and 2 cups panko (Japanese breadcrumbs)on 3 separate trays or bowls. Take the patties out of the refrigerator and dip each patty in the flour, beaten egg, and panko, in that order.
2. Now they are ready for deep-frying.

To Deep-Fry

1. To a wok or a heavy-bottomed pot, add 3 cups neutral oil or enough for at least 2 inches (5 cm) of oil in the wok/pot. Bring the oil to 340–350ºF (170–180ºC) over medium or medium-high heat, using an instant-read cooking thermometer to check the temperature. Then, deep-fry the Korokke in batches until they are golden brown. The inside is already cooked, so all you need to do is to fry them until golden brown. Tip: When you deep-fry, do not crowd the pot because the oil temperature will drop quickly. Your ingredients should take up no more than about half of the oil surface area at any one time. For more helpful hints, read my post How to Deep-Fry Food.
2. Transfer the Korokke to a wire rack or a plate lined with paper towels to drain the excess oil. Continue deep-frying the rest of the patties. Serve immediately with tonkatsu sauce.

To Store

1. You can store the leftover in an airtight container and freeze up to a month. To reheat, put the frozen or half-defrosted Korokke on a baking sheet lined with aluminum foil or parchment paper and bake at 350ºF (180ºC) for 15 minutes or until the inside is warm.