Peel and cut the eggplant into ¾ inch cubes, put the pieces in a colander, sprinkle them well with salt, and let them sit for a ½ hour in the sink, while the salt draws out the bitter juices. Rinse and pat them dry.
Set pasta water to heat, salt it when it boils, and cook the bucatini.
While doing this, cut the sausage into bite size pieces, add the eggplant and a couple of tablespoons of olive oil, and sauté the mixture until the sausage begins to brown and the eggplant has wilted.
Add the tomatoes, thyme, basil and continue cooking covered for about 10 minutes, adding a little more liquid if the sauce looks like it's drying out. When the pasta is done, season it with the sauce and serve it with the cheese on the side.