What's a good substitute for Spanish onions?
In my 50+ years as a food-a-holic, this is only the second recipe that lists Spanish onion as an ingredient. The first was the terrific Shrimp Provincale (sic) in Craig Claiborne's 1973 reprint of "Cooking with herbs and spices." That recipe sent me on a lifelong search for Spanish onions at the grocery stores in San Francisco (successful) and Asheville (futile). For the shrimp dish, which calls for raw Spanish onions, I've substituted red onions with good results.
Here's my question for the cooked Spanish onions in Ina's recipe. Can I find them by another name in local grocery stores and, if not, what is the nearest substitute?

Recipe question for:
Ina Garten's Pasta alla Vecchia Bettola
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2 Comments
Your best course of action might be to ask your local grocer (a gourmet type place rather than a supermarket) or visit your local farmers market and look for a stand that sells multiple varieties of onions since the varieties I mentioned might not be available in your area.
There's also the issue of seasonality where the varieties I mentioned aren't available all year long. Cost might also be a consideration since it might be a long trip from Maui or Washington state to where you live. Might better to seek something grown in your neighborhood.
Best of luck.
I found a couple responses...some say use a sweet onion, others say they are pronouncedly sweeter than Spanish.
Most say a yellow onion or shallots as good substitutes.
One gave a good description of why Spanish onions are different - grown in low sulfur soil, which lets sweetness come through.
https://earmata.com/difference-spanish-onion-yellow-onion/