Eggplant is never better than in mid-summer, locally grown.  So here's a classic dish with a few innovations.  First, eggplant is soggy if just sliced, doused with EVOO and baked.  It only gets soggier when it is combined with sauce and cheeses and then baked again as a casserole, which is what we have in mind.  Second, according to The Little Woman, a robust Italian tomato sauce must have some ground beef in it.  Third, mild Italian sausage plays off admirably against the sauce, cheeses and the crispy eggplant. 
So here we have:
 

EGGPLANT PARMIGIANO
See abbreviations, if needed

2          eggplants, sliced ¼ inch thick 
1T        coarse salt
1C        AP flour 
4           eggs, beaten
8oz       Panko or other bread crumbs
1C        grated Parmigiano Reggiano
3           medium spicy Italian sausage links
2T        EVOO
1          red or green pepper, diced
2          cloves garlic, pureed
1          red onion, diced
½ Lb   ground beef
30oz    canned diced tomatoes
6oz      canned tomato sauce
1T       Italian herb blend (oragano, basil, marjoram, thyme, rosemary)
6oz     diced mozzarella

FOR THE EGGPLANT: 
1.  Toss eggplant slices and salt until combined, than transfer to large colander 
     Let stand 30 to 45 minutes. Then pat dry, brush off salt residue and set aside
2.  Set up an "English Breading Station":  (three pie plates: a, b, and c)
      a.  flour and S/P
      b.  egg wash
      c.  Panko and a little of the Parmigiano Reggiano
3.  One at a time: Flour an eggplant slice, then transfer it to the egg wash plate, then coat it 
     thoroughly in the Panko plate
4.  Place all slices on a sheet pan with parchment paper.  Or on a sheet pan greased with EVOO
5.  Bake the eggplant in a preheated 425F oven for 30 minutes, turning the pieces at 15 minutes, 
     and then remove the crispy eggplant but leave the oven on

FOR THE SAUCE: 
6.  Place sausages in pan of water and BTB, cool, peel and slice into bite sized pieces
7.  In a large evaseé like pan, sauté diced onion, pepper and garlic in EVOO, 
     to translucent and then hold 
8.  In a frying pan, sauté ground beef in EVOO, drain and transfer to evaseé
9.  To the evaseé, add diced tomatoes, tomato sauce, S/P, Italian herbs and then
     BTB, add sausages, then reduce heat and simmer about 45 minutes 

TO ASSEMBLE:
10.   Spread some tomato sauce in the bottom of large buttered baking dish
11.  Layer in half of the eggplant slices
12.  Add more sauce over the eggplant, then sprinkle with half of the mozzarella
13.  Layer in remaining eggplant and some more sauce but don't drown this top layer
14.  Sprinkle with the remaining Parmagiano Reggiano and the mozzarella
15.  Bake at 425F until bubbling, about 15 minutes 
16.  Brown top under broiler
NOTE:  The crispy eggplant takes a little more time, but it's worth it.