Slice the pumpkin into 7mm thick pieces. Cut the eggplants in half, remove the stems, and make diagonal cuts on the skin. Halve them again.

Season the pork slices with salt and pepper, then shape them into 2cm diameter balls. Coat them with potato starch (approximately 8 balls).

Mix the ponzu sauce and water in a tray.

Heat salad oil in a frying pan over medium heat. Cook the pumpkin, eggplants, and cherry tomatoes for 2-3 minutes per side until cooked through. Immediately dip them into the sauce mixture while hot.

In the same pan, cook the pork balls over medium heat, turning them to brown all sides. Add sake, cover with a lid, and steam on low heat for 3 minutes. Remove the lid and stir-fry lightly. Dip the pork balls into the sauce mixture while hot.

Cover the tray with plastic wrap and refrigerate for 1 hour to let the flavors meld.