Wash eggplant. Poke holes into eggplant randomly with a fork. Place eggplant on a cookie sheet which has been covered with aluminum foil.
Roast the eggplant until it is thoroughly cooked and collapses (about 30 to 40 minutes).
While the eggplant is roasting, mash garlic and salt with mortar and pestle until it becomes pasty.
To cool eggplant quickly, slice in half, and leave draining in the sink in a colander. When cool, peel the skin off. Chop eggplant into medium-size chunks.
In bowl, combine eggplant and garlic, mashing eggplant and stirring the garlic throughout. When it is consistently mushy, mix in the lemon juice, olive oil & the chopped walnuts to add crunch and texture.