I used to watch Top Chef religiously. But a few seasons ago, I just had to roll my eyes. Guest judge Martha Stewart challenged the chef-testants to create a one-dish meal. Without exception, here’s how they did it:

  1. Make sauce in a pan.
  2. Move sauce to a bowl and wash pan.
  3. Saute onions and garlic in washed pan.
  4. Move onions and garlic to a bowl and wash pan again.
  5. Heat oil in washed pan. Sear a big chunk of meat in it.
  6. Move meat to a bowl and wash pan a third time …

I’m sorry, but to my mind, that is not one-dish cooking. (And if it is, no wonder people fear the kitchen!)

A one-dish meal for me means exactly that. One dish. Start to finish. My favorite is a 13x9x2-inch Pyrex casserole or — If I’m feeling fancy — a 13-inch oval baker by Emile Henry. Give me that, a knife and a chopping block, and I’m all set.

One-dish suppers are lifesavers when you’re staring down 6 p.m. with only the vaguest idea of what’s for dinner. Here, one of my family’s favorites. This dish segues from season to season, capitalizing on the ingredients that are freshest and most local at the grocery store. It’s infinitely adaptable. And it’s easy! No measuring, no fancy gadgets … and no washing the same bowl over and over again.

I think that maybe, Martha Stewart would be proud.

Fish & Vegetable Gratin (serves 4)

Preheat oven to 400 degrees.

Generously oil a 13-inch baking dish.

onedish1Cut 2-3 yellow- or red-skinned potatoes into 1/4-inch slices. Choose a couple of other vegetables to slice into similarly sized rounds. I use zucchini and yellow squash in the summer; I used eggplant and fennel last night. Finally, slice 2-3 tomatoes into 1/4-inch slices and briefly blot them between paper towels to absorb excess liquid.

Lay the vegetables in concentric circles around your dish, overlapping onedish2slightly, until the entire bottom surface is covered.

Finely chop half an onion and 2-3 garlic cloves. Sprinkle over the vegetables, then sprinkle on a couple of tablespoons of fresh herbs or 1 teaspoon dried. (I use fresh basil, thyme and rosemary in the summer; last night I used dried basil and oregano.)

Drizzle everything generously with olive oil and 1/4 cup chicken or vegetable broth. Season with salt and pepper. Cover the dish tightly with foil and roast for 40 minutes.

onedish3Meanwhile, pat 4 cod or tilapia fillets dry with paper towels and season with salt and pepper. Grate some lemon zest over the top of the fish or some minced preserved lemon.

After 40 minutes, remove the foil from the vegetables. Lay the fish on top in a single layer. Drizzle with preserved lemon juice, if using, or with olive oil.

Bake, uncovered, 10 minutes, or just until the fish is cooked through. Let sit for 5 minutes before serving.