Eggplants are porous and have several tiny holes that soak in oil and water, often making them soggy. Brining them in a saltwater bath will produce sturdier eggplant slices.
It may sound counterintuitive to soak the eggplant in water to prevent it from being mushy, but salt brings out the excess moisture and rids the eggplant of its bitter taste.
After slicing and rinsing your eggplant in cold water, fill a bowl with lukewarm water and salt it heavily. Then, pat the slices dry before placing them in the saltwater bath.
Once the eggplant has been soaking for around 30 minutes to 1 hour, pour out the brine. Rinse the slices with cold water to remove excess salt, then pat dry.