Wash eggplants and tomatoes. Preheat the oven to 350℉
Peel the eggplant and cut them into slices. Set aside
Lay them on a baking sheet with parchment paper, bake them for 15 minutes. Flip the eggplant slices halfway. Or add about 1 tbsp of salt and wait 10 minutes
Cut tomatoes into chunks. Mince the garlic.
Add the garlic, black vinegar, sugar, soy sauce, water and cornstarch together.
After 15 minutes take the eggplant out of the oven. If using the salt method, just squeeze the eggplant.
Put some oil into a wok. Stir fry the eggplant for 2 minutes on medium high, add in the tomatoes and stir fry for another 2 minutes or until it softens.
Add in the sauce and let it simmer on medium low heat. It will take about 6-7 minutes
Add salt to taste and serve with rice.
Notes
A hack: if short on time, you can make the sauce without the cornstarch the day before, store it inside the fridge in an airtight container and then add cornstarch to it when you are ready to cook.