“Tonnato” sauce is a mayonnaise with garlic, anchovy and capers that includes some cooked tuna as well. In Italian cooking it’s often served with sautéed veal, but here I’ve adapted it as a complement to grilled tuna. The rich tuna can stand up well to strong flavorings such as those in this sauce. This dish was a very popular menu item with the guests this spring at Rendezvous.

Grilling the tuna:

 Use one 5-6 ounce tuna steak (1 1/2” thick) per person. Sprinkle them lightly with salt and pepper and drizzle with a little olive oil. Grill them over a medium fire for 2-3 minutes on both sides. The tuna will remain red through the middle, like rare to medium-rare beef.

 Serve the grilled tuna steaks with the Tonnato Sauce (recipe follows) and a wedge of lemon.

1 tablespoon  smooth mustard

1 tablespoon  grainy mustard

       juice of 1 lemon

Mince together the tuna, anchovy, garlic and capers. Transfer this mixture to a medium bowl and add the mustards and egg yolks. Slowly whisk in the olive oil as per making a basic mayonnaise. Balance the seasoning with lemon juice and salt.

1 head escarole, cut crosswise into 1” pieces, rinsed and drained

1 cup fresh-picked flat leaf parsley leaves, rinsed and drained

1/2 cup Reggiano parmesan, shaved with a vegetable peeler

 Slice the raw asparagus very thin on a sharp diagonal. Put it into the salad bowl, drizzle some of the vinaigrette and sprinkle salt lightly over it. Prepare the escarole and parsley and add them to the asparagus. Dress this with the vinaigrette, season lightly with salt and pepper and toss. Put the shaved parmesan on top.

 I prefer young escarole for this salad because of its great combination of crunch and light bitter flavor. Radicchio is a good addition to this salad, and bibb lettuce is a suitable substitute. Sometimes I sprinkle toasted breadcrumbs over the top of the salad as a final touch just before serving.

Lemon-herb vinaigrette:

2 tablespoons  lemon juice

1 tablespoon  fresh minced herbs (thyme leaf, chives, chervil)

Combine all the ingredients in a small jelly jar with a screw-on lid and shake well. Season to taste with salt and pepper.

 A simple and delicious way to prepare young potatoes such as Yukon gold, red-skinned or fingerling potatoes is to cut them into thick (1/2”) rings and simmer them in salted water with one clove of sliced garlic and a tablespoon of olive oil. When the potatoes are tender enough to pierce easily with the tip of a knife, drain them and serve immediately with the grilled tuna and the asparagus salad.

 Steve Johnson is the owner-chef of Rendezvous restaurant, 502 Mass. Ave. (Central Square)in Cambridge.