Let’s cut the vegetables and mushrooms. Cut each of the bell peppers in half lengthwise. Remove the stems and the seeds. Clean the inside of the bell peppers.
With kitchen scissors, remove each of the stem ends from the shiitake mushrooms. Cut off the stems of the shiitake mushrooms.
Thinly slice the stems and cut them into fine strips. Chop them into fine pieces.
Make vertical cuts in the onion, slice across the initial cuts and chop it into fine pieces.
Let’s make the ground meat mixture for the stuffing. Combine the salt, pepper, sake, beaten egg and soft bread crumbs in a bowl and stir together with a spatula.
When combined, add the ground beef and pork mixture and mix thoroughly until it begins to become gooey.
Add the chopped onion and shiitake stems to the mixture and lightly mix.
Finally, flatten the meat mixture in the bowl with the spatula.
With a fine mesh strainer, dust the inside of the bell peppers and mushrooms with flour. This will help hold the meat in place while cooking.
Let’s stuff the meat into the peppers and mushrooms. Divide the meat mixture in half with a spatula. With your hands, shape one half into an oval.
First, stuff three of the bell pepper halves with the meat mixture.
Next, stuff two of the shiitake mushrooms.
Press the meat into the peppers and mushrooms with the spatula completely filling in all of the gaps. Repeat this process with the rest of the meat mixture and stuff all of the peppers and mushrooms.
Dust the surface of the meat with flour again. This will help the meat become golden brown and prevent the juices from evaporating.
Let’s make the sauce. Combine the soy sauce, mirin, sake and sugar in a bowl and stir together with a spatula.
Let’s fry the meat. Add the vegetable oil to the heated pan.
Swirl the pan to coat with the oil. Gently press the stuffed peppers and mushrooms onto the pan with the meat side facing down. Fry the meat on medium heat.
When the meat becomes golden brown, gently flip them over. Fry the other side of the peppers and mushrooms until lightly brown.
Remove the excess oil with a paper towel.
Add the sake and cover with a lid. Reduce the heat, and cook the meat for about 2 minutes.
Let the alcohol evaporate and remove the lid. Gently press the meat with kitchen chopsticks and check if the juices are clear.
Turn off the burner and place the stuffed peppers and mushrooms on a plate.
Turn on the burner again and heat the sauce in the pan. Reduce the sauce while stirring with the spatula.
When large bubbles form at the top and it has thickened as shown, turn off the burner and pour the sauce onto the meat. Sprinkle on the seven flavor chili powder and enjoy the stuffed peppers and mushrooms.
After removing the meat from the pan, use the remaining savory juice in the sauce for added flavor.
This recipe is also delicious when cooled and it is one of the best ingredients for a bento lunch box.