Gather all the ingredients. Cut the garlic into thin slices and combine the stir-fry seasoning in a bowl.
To Make Pork Marinade
In a medium bowl, combine soy sauce, sake, potato starch and mix all together.
Add the ground pork and mix well. Set aside.
To Make Stir Fry Sauce
In a small bowl, combine sake, soy sauce, oyster sauce, and gochujang.
Add sugar and mix all together. Set aside.
To Prepare Kabocha
With a spoon, remove the seeds from the kabocha. Cut the kabocha block in half so it's smaller and easier to slice. Tip: We eat kabocha skin in Japan! If there are tough scars on the skin, shave them off. We remove the skin only when you want to feature kabocha's yellow-orange color such as kabocha soup or kabocha pie or pudding (the color won't be pretty if you mix in green skin).
Cut the kabocha into thin slices, roughly ⅛ inch (3 mm) thickness. If the kabocha pieces are too big, cut them in half.
In a microwave-safe glass container, put kabocha slices and 1 Tbsp water. Place a paper towel on top and microwave for 2 minutes (depending on your microwave wattage).
Check kabocha's doneness with a wooden skewer. It should be 80% cooked through (as we will stir-fry later). Do not overcook them because they will break into pieces during stir fry.
To Stir Fry
In a large frying pan, heat oil on medium heat and cook garlic until fragrant.
Add the marinated meat and cook until no longer pink.
Add kabocha slices and coat them with oil.
Cook covered on low heat until kabocha is fully cooked, roughly 5 minutes.
Insert a skewer to check the doneness. Add the stir fry seasoning.
Increase the heat and stir fry to coat the ingredients with the sauce. When the sauce has reduced, it's done.
Transfer to a serving dish. Enjoy!
You can keep the leftovers in an airtight container and store in the refrigerator for up to 3 days or in the freezer for a month.