Today I wanted to make that sesame-ginger dressing they use at good sushi bars and Japanese steak houses. I looked around on the Net and found a few alarming varieties, including more than one with ketchup as a main ingredient. Huh? Since when was ketchup a traditional Japanese ingredient? I’m all for “fusion cuisine”—unless it means Americans squirting ketchup all over the world’s food.

And that’s what appears to be happening. Karl and I were in a dubious Mexican restaurant in Portsmouth, NH a while back and we encountered ketchup in our enchiladas. Granted, the place wasn’t trying to be anything more than a sports bar, and this was about as far as we could get from Mexico, and enchiladas do involve tomatoes in some capacity, but ketchup? I was disgusted.

Ketchup evokes strong American memories from my childhood, like afternoons at the Tennessee state fair with corn dogs, fries, and funnel cakes, a summer day on the beach in New England with a sandy hot dog, or a messy 4th of July hamburger and Fritos on a paper plate with a can of Coke. I love these traditional American dishes, but they’re in vomitive dischord with my favorite ethnic food experiences: eating tacos made with chopped onion, avocado, cilantro, lime, and beef on a flour tortilla, visiting the Chinese tea house for a solemn three hours of meditation around a pot of jasmine tea, or picking plates of raw fish from an indoor stream at a minimalist urban sushi bar.

The irony is that ketchup began its life in Asia as ke-tsiap a few hundred years ago, though back then it was a pickled fish sauce without tomatoes. But that was a few hundred years ago, and this is now, and I doubt whether our circa-1870s varient of ketchup has a place in old-world cuisine. Yet I’m surprised by the frequency with which it appears in intriguing (disgusting) ways in “ethnic” online recipes from all over. Isn’t this sacrilegious? Or am I just being a curmudgeon as usual?

My theory is that English translators of recipes made before the 1980s knew you couldn’t find white miso paste or caper berries or fish sauce outside of the biggest cities, so in order to reach the widest audience they said, “No problem, just put ‘ketchup’ instead, nobody will notice.” And this is how world cuisine came about: When you don’t have something needed to make a dish in the traditional style, you need to improvise with whatever’s locally available. Now you have something new!

Which is why I’m now paranoid in restaurants, always peering under the sashmini for a hint of Heinz, or directing a suspicious eye toward the red soup paste on the table at the Vietnamese restaurant. We have assimilated traditional food from other cultures into our cruel, thankless culinary melting pot, and I’m not going to sit idly by while we ruin meal after meal. I want to catch the cooks red-handed, the ketchup still oozing from their plastic squeeze bottle into the bowl.

But deep down I know I should be forgiving. Taste conquers all in the end, doesn’t it? And surely someone more meddlesome than me is probably mixing up an incredible ketchup-laden Korean-inspired beef marinade or ketchup-infused red wine reduction as I write this.

So lets get back to ginger-sesame dressing. After picking what I liked out of the online recipes, here’s the dressing I ended up making. Throw some stuff into the blender: a chopped shallot, a small chopped carrot, an inch or so of minced ginger (about 2T), juice of a lemon, 2T rice vinegar, 1/2 cup sesame oil, a couple teaspoons of toasted sesame oil, if you have it, and blend. Add salt and black pepper (or even some chili oil/paste) to taste.

PS. For great ketchup recipes, check out Jeffrey Steingarten’s The Man Who Ate Everything.