Put half the oil in a large skillet or wok over medium-high heat.
When hot, add the shiitakes, season with salt and pepper, and cook, stirring occasionally, until the mushrooms are browned and crisp, about 5 to 10 minutes.
Remove with a slotted spoon and set aside.
Add the remaining oil to the skillet. A few seconds later, add the garlic and ginger (if using). As soon as they sizzle, add the eggplant chunks.
Cook, stirring every minute or so, until the eggplant is nicely browned on all sides, about 5 to 10 minutes.
Stir in the chile paste (if using) and the vegetable stock.
Stir well, scraping the bottom of the pan to release any flavorful browned bits.
Bring to a simmer, then reduce the heat, cover, and cook until the eggplant is completely tender, 10 to 15 minutes more.
Add a splash more stock if the pan becomes too dry.
Gently stir in the soy sauce and the tofu cubes.
Continue to cook, stirring occasionally, until the tofu is heated through, about 5 minutes.
Turn off the heat and stir in the reserved crispy shiitakes.
Taste and adjust seasoning if necessary.
Garnish with sesame oil, cilantro, toasted sesame seeds, and scallions as desired, and serve immediately.
