Wipe the eggplant clean and slice them in half lengthwise. With the tip of a knife, score the flesh deeply in a diamond cross-hatch pattern by making two or three long cuts, cutting at a steep angle, and then rotating the eggplant to make another set of similar cuts. Press on the edges of the halves to open the cuts and sprinkle salt (1 to 1-1/2 tsp. total for all the halves) over the surface and into the cuts. Set aside, cut side up, for 30 min. Heat the oven to 400°F. Line a baking sheet with parchment.