What is parmigiana di melanzane, and why does it take so long?

Parmigiana is the dish people make for occasions and then wonder why they don't make it every week. The answer is in the method. It is not complicated, but it is a series of separate jobs, and the most time-consuming of them, frying the aubergine, is also the one that makes it so good.

What it is

The Treccani dictionary describes parmigiana as a dish in which sliced vegetables are floured, sometimes dipped in egg, fried, and then layered in a baking dish with tomato sauce, plenty of Parmigiano and sometimes mozzarella, before being baked. Aubergine is the best-known version; Treccani also mentions courgettes and cardoons. The aubergine version is parmigiana di melanzane, or melanzane alla parmigiana.

Where it comes from: the friendly debate

Despite the name, Parma's claim is not the only one. Wikipedia's parmigiana entry explains that the dish is variously attributed to Campania, Sicily or Parma. The Parma link is the cheese. One Sicilian explanation traces the name to parmiciana, a word for the slats of a louvered shutter, which the overlapping slices resemble. The food writer Clifford Wright, as Wikipedia reports, points to 19th-century Neapolitan cookbooks. Nobody has settled it, which is one of the pleasures of eating it in different places and hearing each one claim it.

Regional versions differ in the details. Wikipedia notes that Neapolitan versions rarely bread the aubergine before frying, and that Campania also has a "white" parmigiana with no tomato. Some versions layer in hard-boiled eggs; some use different cheeses. The constants are aubergine, layers and the oven.

Why it takes so long

1. Slicing and salting. The aubergine is sliced, and many cooks still salt it and leave it to drain, then pat it dry. In our experience today's aubergines are seldom bitter, so this is optional (see salting aubergine), but it helps the slices brown and absorb less oil.
2. Frying in batches. Each slice is fried until golden on both sides, a few at a time, then drained. For a full dish, this is the longest stage by far.
3. The sauce. A simple tomato sauce with basil, simmered until it is thick enough not to make the layers watery.
4. Assembly. Sauce, aubergine, cheese, repeated until the dish is full, with sauce and Parmigiano on top.
5. Baking. Until bubbling at the edges and golden on top.
6. Resting. This is the step people skip. A parmigiana straight from the oven slumps when cut. Left to settle, it slices cleanly, and the flavours come together.

Where you can save time

• Roast or grill the aubergine instead of frying. Brush slices with oil and roast them on trays in a hot oven, turning once, until soft and browned. It is much less hands-on, and you can do all the slices at once. The result is less rich and silky than fried, but very good. Our guide on aubergine that isn't oily has more.
• Use a good tin or jar for the sauce. A passata simmered with garlic, oil and basil is entirely traditional in spirit. No shame in it.
• Skip the salting if the aubergines are fresh, firm and glossy.
• Make it ahead. Assemble and bake a day before, cool it, cover and refrigerate. Reheat until bubbling. Many people prefer it the second day, when it holds together better.
• Make a big one. The effort barely increases with size. Leftovers keep well in the fridge for a couple of days.

Avoiding a watery parmigiana

• Pat aubergine slices dry before cooking.
• Cook the sauce until thick.
• Drain mozzarella well and tear it into small pieces, or use a drier melting cheese.
• Don't overfill each layer with sauce.
• Rest it before cutting.

How to serve it

Warm or at room temperature, never piping hot. A square of parmigiana with bread and a green salad is a complete dinner. Cold leftovers in a sandwich are a private joy.