I've never had that problem with my Kirkland set from Costco.

From the almighty eGullet Cookware primer:

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Stainless Steel Body with an Aluminum Base
- This design begins with durable, nonreactive stainless steel and adds the thermal benefits -- evenness of heat, high specific heat per cubic centimeter, responsiveness -- of aluminum to the bottom of the pan.
- Because the aluminum base only covers the bottom, virtually no heat is conducted from the base up into the heavy stainless steel sides of the pan.
- Moderately expensive to expensive.
- Things to consider: 1) Due to the way this cookware is manufactured, the aluminum disk can never quite cover the entire base of the pan. The percentage of the base covered by the aluminum disk varies from manufacturer to manufacturer and is one indication of quality. 2) Cooks are sometimes apprehensive that foods will scorch and burn on the parts of the pan that are not covered with aluminum -- namely the sides and the portions of the base not covered by the aluminum disk -- because these are essentially plain stainless steel. This is only possibly a concern in conditions where the flame heating the pan is larger than the pan itself, and significant heat from the heat source is in direct contact with those portions of the pan. Such conditions are rare in the home kitchen, and can largely be mitigated by adjusting the flame appropriately and not using pans of this design that are too small in diameter for the stove on which they will be used. 3) Some manufacturers claim to employ special âÂÂmulti-layerâ bases that are better than pure aluminum bases. DonâÂÂt be fooled by this marketing ploy. The bases on these pans are 99% the same as those employed in the other aluminum disk bottom designs.
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Short answer: Burnt food around the edges of disk-bottomed pan can usually be pinned on operator error.

wolfgang, yes, the disc helps enormously to both spread the heat and prevent hot spots. The disc also 'stores' some heat so that if you add food, the temp. doesn't drop. However, the stainless sides above the disc might get too hot, particularly if the stainless is very thin. Sometimes (more likely with gas flames?), the sides might get hot enough to burn what you're cooking.

The solution? Lower cooking heat, or use a different pan, perhaps a triply, or a duel-ply (stainless/aluminum.

Disc bottoms are good for non-stick egg/omelet/pancake pans, because you're not using the sides. Also tall sauce or stock pans that cook all day but don't get too hot.

Better disc bottomed pans have thicker sides. See the e-gullet article.

Here is a link that might be useful: cookware lecture e-gullet

Thank you for your replies. I stumbled upon the e-gullet lecture and read it and the 18 pages of questions last week. I just figured that if anything, the part of the pan without the aluminum underneath to conduct the heat would be colder than the middle.

I only have one decent piece of cookware at the time--an AC 12" SS frypan--and I'm looking to add in the very near future 2 sauce pans (Paderno GG is in 1st place right now but may get one GG and one Sitram Catering). I use sauce pans mostly to reheat soups and stew type dishes so I'm not using a lot of flame and therefore I shouldn't have a scorching issue.

I have some Sitram and an electric smoothtop range. I have had no burning around the edges, as you mentioned, with my Sitram. I have learned what temps work best with my pans and range and have adjusted my cooking habits to work with them.

The copper disks on my Demeyere Atlantis pans go all the way to the edge of the pan. I've never had any problem with burning around the edges. (Or any sort of unevenness at all, for that matter--2mm of copper is really good at spreading the heat around.)

I've attached a link to Demeyere's description of how their disk bottoms are constructed.

Here is a link that might be useful: Demeyere disk bottoms

And, you can see some decent pictures on this page. (Someday I'll figure out how to include links in the body of a post, so I don't have to make multiple posts for multiple links.)

Here is a link that might be useful: Altantis at 125 West.

Someday I'll figure out how to include links in the body of a post, so I don't have to make multiple posts for multiple links.)

Just for you, solarpowered, because I always enjoy you info on cookware:

To include a link in the body of your post is easy. My instructions look complicated only because I have to separate them carefully. I do this all the time, and it takes a couple seconds. Follow these steps, using a space ONLY where indicated:

Step 1: type this symbol: Step 2: follow that with the letter "a" (don't use quotes)

Step 3: follow that with one space and then "href" (don't use quotes)

Step 4: follow the href with an equal sign

Step 5: cut and paste your desired url here

Step 6: close the url with this symbol: >

Step 7: type the word you want your link to be embedded in (e.g., Demeyere)

Step 8: Now close by first typing the symbol: Step 7: then type a slash mark

Step 8: then type the letter "a" (no quotes)

Step 9: then close with the symbol: >

It will look like this.

I just want to note that I've used cheap Macy's "tools of the trade" disc bottoms and the stainless sides seemed to get hotter than the bottom. Milk would sizzle and splatter when I poured from a disc-bottomed sauce pan. and tomato sauce would start to burn (around the edges) in a fry pan. Just my experience ...

Well I'm all about cooking on high and use what burner and pan come to hand so I'm the "operator error" he's talking about. :)
I move around some for my job and go back and forth between gas and electric (prefer smooth top for easy cleaning but IME the tend not to heat up as fast or get as hot)
Personally if I'm going to spend a lot on a pan, I don't want to have to worry about the kind of fiddly operator errors egullet is talking about. I have enough worries with the rest of it.

Thanks Suzyq!