Induction will have the issue. In this regard, it is no different that any other kind of non-bridged burners. The nature of cast iron is that it is very good at absorbing and retaining heat but not so great at spreading it.

Another couple of thoughts.

Somewhere recently I read about a reasonably priced griddle of magnetic steel wrapped around a large aluminum slug which apparently does a pretty good job of spreading heat on spanned burners including induction. (Not turning up in a search at the moment, though. I'll post back if I can locate it.)

What is the problem with the cut-out? Is it too large for other current 36" induction cooktops? If so, it may be possible (and inexpensive) to have metal shop fabricate a stainless steel collar that takes care of the problem. (Again, a solution I saw discussed here last fall but I'm not finding the thread yet. )

As a supplement to jwvideo's comments, I would add the following:

The Electrolux Icon surface and cutout sizes are matched by their Frigidaire brand Gallery and Professional cooktop models. The Bosch Flexinduction surface is almost the same size as the Electrolux, but the specified cutout is smaller. I didn't delve into schemes (if actually needed) for the Bosch that would accommodate the cutout difference.

Here is a table from an earlier thread that provides some relevant comparisons. Click on the table to magnify it. You may wish to compare dimensions with those of your Kitchenaid electric cooktop.

Cooking across hobs on the Frigidaire models might be a stretch (literally) due to generous spacing. A long aluminum electric griddle may be a better choice for some foods such as pancakes.

The Frigidaire and Electrolux all have 10-inch hobs that will likely function ok with a significantly larger pot. Just how big are your pots across the bottom flat?

kas

jwvideo - I may need to look into the griddle you mentioned. Sounds like it might work for us. And my current cutout is HUGE, 35.6" x 20.5".. I have a counter guy trying to match the granite we currently have so I can get the cooktop I want but I'm not holding my breath on this one. Thanks for your information!

Kaseki - Excellent information, thank you. I originally wanted the Bosch NITP666SUC, unfortunately the current hole being so large made that model impossible without some type of counter top modification. That being said we just got back from Sears and looked at the Electrolux clone. It comes with a bridge element, so I may see about this one. Thanks again for your information, very helpful!

Michelle Mullins: If you come across any Internet technical information about the Sears Electrolux clone, please let us know. When I produced that table, I was unable to find any data on Sears web sites.

If you buy it, then I would greatly appreciate your letting us know from the literature provided with the cooktop what the table parameter values are.

I can happily add another column to the table.

kas

Why not buy a presto countertop grill? As Minnie up thread said.