I imagine that there is nothing more stressful than the first time you cook for your beloved's mother. After all, you are proving yourself in that most elemental of areas - the nourishment of the very child that she fed for so long. That phrasing veers a little too close for comfort to the idea that Ben is a child that I take care of. Nothing could be further from the truth, in fact, sometimes I think I require a little too much caretaking by him. But still, isn't it one of those long-held cliches that cooking for your boyfriend's mother is an exercise in desperation and fear?

Luckily for me, however, Ben's mother is a lovely woman and a supporter of my kitchen activities, as proved by her donation of this incredible machine that I stop to pet at least once a day. Despite the fact that we live in the same neighborhood most days of the week, I'd never gotten my act together to actually have her over for dinner. But earlier this week, we finally got our schedules aligned and I found myself zipping through my recipe archives for a casual-but-no-spag-bol-please-thank-you-very-much dinner. I settled on a fish recipe that Marian Burros published in the New York Times earlier this summer as an accompaniment to the Times's dissection of which fish were good for eating these days and which should be blacklisted until the end of industrial pollution as we know it.

The recipe called for halibut, balsamic vinegar and spring onions. For the second time in a week, I found myself at Whole Foods, wondering exactly why I had thought it would be a better idea to shop there than anywhere else. The selection of balsamic vinegars was terrible - the prices were either shockingly high or alarmingly low. And when I asked about spring onions, the vegetable stocker looked at me like I might not be right in the head. I assumed the "spring" part of the equation meant that I could make that recipe in May and in May only, but I was proven wrong at the Greenmarket the next day when I saw large bunches of spring onions for sale at almost every stand. At Whole Foods I made do by buying three bunches of scallions to substitute for the onions.

The recipe was easy-peasy. I sauteed the quartered scallions and thyme sprigs in oil until tender and caramelized, then bathed them in a swift bath of vinegar before removing them from the heat. I wiped out the remaining film of vinegar in the pan, then poured in more oil and quickly cooked the fish on both sides before adding a bit more vinegar to the pan. I felt that six whole tablespoons of balsamic might overpower the delicate fish, so I disregarded Burros's step of adding yet more vinegar once the fish was plated. The restraint was a good idea. The balsamic obviously went well with the onions (it's a classic Italian preparation) and the sweet, acidic sauce was nice with the fish, but any more vinegar would have been overkill.

I wished there had been more onions to top the fish with, so I'd say don't take my lead on the scallions. Try for spring onions, and if you don't find those, then use sweet, white onions instead. Cipollini, even! We ate our fish with basmati rice that had been rinsed quite well and cooked in chicken broth, and tender, young zucchini steamed and dressed with a halved garlic clove, olive oil and flaky salt. The best part of the delicious meal? I think Lynn still likes me.

Pan-Fried Halibut with Balsamic-Glazed Spring Onions
Serves 4

4 halibut fillets (about 7 ounces each), rinsed and patted dry
Freshly ground black pepper
3 bunches spring onions
6 tablespoons olive oil
6 sprigs fresh thyme, plus leaves for garnish
Kosher salt or coarse sea salt
6 tablespoons balsamic vinegar (I only used 4)
Fresh chopped chives for garnish

1. Season fish with black pepper. Trim onions, leaving root end intact; remove outer layer. Cut onions into quarters.

2. In a very large saute pan, heat 2 tablespoons oil over medium heat. Add onions and thyme and season lightly with salt and pepper. Cover and cook until almost tender, about 3 minutes.

3. Uncover pan and continue to cook until onions caramelize, about 3 minutes more. Add 2 tablespoons balsamic vinegar to pan, let cook for 10 seconds, then immediately transfer onions to a bowl.

4. Heat remaining oil in pan until very hot. Lower heat to medium-low, add fish skin-side down, and cook until just opaque, about 4 minutes a side. Add remaining balsamic vinegar and remove from heat.

5. Transfer fish to four serving plates and top each fillet with some onion mixture. Garnish with thyme leaves and chives.