Enhance Your Fish -- Yuzu Kosho Butter Sauce

I recently wrote about my new found fondness for Yuzu Kosho, a Japanese yuzu pepper paste. I'd been spreading it on just about everything with abandon. Even baby carrots got a smear. I mentioned that beef was my favorite beneficiary of the Yuzu Kosho, but that was at the beginning of my tryst with the condiment.

Now that we've been together for a while and our relationship has matured, I've had a chance to do some experimenting. Yuzu Kosho doesn't need to be left to its own devices. You can give it a role in something greater.

I had been puzzling over what to do with some swordfish I had picked up at the fish market, when I realized that just spreading the yuzu pepper paste on the fish or adding it to a vinaigrette was perhaps too simplistic. I wanted something to enrich the paste. I felt it could benefit from a more balanced roundness. And what gives body and enriches better than butter?

Nothing, I tell you. Nothing.

But too much butter can be flat or greasy. Lemon and something sharp would add further harmony. I needed something with a kick that wasn't spicy, since I had the heat front covered. I settled upon chives or shallots. The final flavor front would need to be tomato. I love tomatoes with fish. The sweetness and acidity from the tomatoes were perfect with the rich butter, spicy and salty pepper paste, and zingy alliums.

This ultra-simple butter sauce was divine on the swordfish. I made it with chives that night. I decided to mess with the recipe again last night, so I could pin it down for you folks. I used shallots and they might work even better than the chives. We gobbled it up on striped-bass. Again a big hit.

There is a complexity to the sauce that is hard to pinpoint thanks to the yuzu pepper paste. The sauce seems slightly exotic, but not specifically Japanese. I served it in a completely non-asian context both times. This recipe is also not one that you need to save for your friends who can't get enough heat. I don't use much Yuzu Kosho here, just a teaspoonful. There is a pleasing peppery quality, but the sauce is not spicy.

Yuzu Kosho Butter Sauce

5 tablespoons butter

2 tablespoons shallots (or chives), minced

1 teaspoon Yuzu Kosho

Juice of half a lemon, or more to taste

15-20 cherry tomatoes, halved

Salt and freshly ground pepper to taste

Melt the butter in a small sauté pan over medium heat. Add the shallots and cook for 2 minutes. Add the Yuzu Kosho and stir to combine. Add the lemon juice and cherry tomatoes and heat until the tomatoes just begin to wilt a bit. Season to taste with salt (you shouldn't need much) and freshly ground pepper. Serve over fish like swordfish or striped bass.

Enough for 3 portions of fish