The Mediterranean summers in my part of Pennsylvania allow us to grow many varieties of eggplants. Dips like this one first appear in local cookery in the nineteenth century, when the Philadelphia Style first emerged from classical French cuisine. I have served this recipe many times, because it is a perfect addition to a summer buffet. It can be served hot on toast like bruschetta or at room temperature as a cocktail spread. A hint to the host: Its flavor improves if made a day ahead.

Instructions:

1. Preheat the oven to 225°F. Cut the eggplants in half lengthwise and lay them cut side down in a baking pan. Add 1 cup water and cover the pan tightly with foil. Bake until soft, 45 to 50 minutes, then scoop the pulp from the skins and transfer to a food processor. Puree until smooth.
2. In a large stewing pan, heat the oil over medium-low heat. Add the onions, cover, and sweat slowly in the oil just until transparent, 4 to 5 minutes. Stir in the pureed eggplant, tomato paste, vinegar, garlic, sugar, salt, pepper, nutmeg, and optional cayenne, if you like a little heat. Cover and cook over a low heat for 10 minutes, to heat the ingredients through and blend the flavors; stir frequently to keep the paste from scorching. Remove from the heat, cool to room temperature then cover and refrigerate for up to three days. Serve at room temperature on crackers or flatbread, garnished as desired.