I have had pretty consistent success with making macarons using the recipe from Bouchon. Whether I let the shells dry or not, age the egg whites or not, the shells always come out around the same texture and very rarely crack.
What I am running into problems with is this:
I currently only have two baking sheets. To bake the macarons, I pipe onto the first cold sheet and stick it in the oven. While they're cooking, I pipe onto the second cold sheet. Both of these batches come out perfect (save for a few cracked shells due to my uneven oven :-P). When I take out the first sheet, I let the macarons cool, move them to a plate, and pipe the next batch. Same with the second sheet. These last two batches, piped onto the hot baking sheets, ALWAYS come out lop-sided. They rise unevenly, and many only get feet on half of the shell.
Is this unevenness due to the fact that I am piping onto a warm baking sheet? Or is it because the batter is sitting out for 20+ minutes before the third and fourth batches are piped? Everything else about these shells is virtually perfect--no hollows, great texture, shiny top.
How do I avoid this in the future?? More baking sheets??
So to test your hypotheses:
1) Make a batch of batter, let it sit 20+ minutes, pipe onto cold baking sheet and bake.
2) Put empty baking sheets into oven at same temperature, for same time as for baking macarons. Make a batch of batter. Take baking sheets out, pipe fresh batter onto warm sheets.
If 1) gives you good results, then it is the warm baking sheet, and you need to buy more sheets. If 2) gives you the good results, then it's the batter sitting around that's the problem, and you either need more sheets so you can bake the whole batch at once, or make batter in smaller batches.
(If they both give you good or both give you bad results, then it's something else you haven't thought of yet!)
Are you using parchment? I find that when I bake my macaron, I use those cookie sheets that are insulated and use parchment. However, I use 6 separate cookie sheets because I bake a bit..and towards the 3rd or 4th batch, my oven gets hotter so I make allowances for the time by baking a minute or so less. I don't pipe onto a hot sheet..I always pipe then let the macaron "set" at room tempture for at least an hour.
I'm guessing it's the hot baking sheet. Suggestions range from 20 minutes to 2 hours re: sitting out time. So that shouldn't matter much.
Are you able to bang/rap the hot baking sheet?
I'm thinking best way is to prep all of your macarons on paper - pipe, rap, then slide the paper off the first two. Then once you piped remaining two sheets either bake those, or replace them with the first two.
Either way I think you need to let those pans completely cool...
Ok I just reread what you wrote. Sounds like your leaving the batter in the bag while the first batch bakes. I think it's a combo of that and hot baking sheets. So I stand by my suggestion. Good luck!
Macarons are finicky for sure - I'm impressed you don't get hollows, that is always my problem - perfect looking from the outside, hole on the inside. But not always, sometimes they work just right.
I'm seconding the hot pan. I don't think it would take much to get them to puff unevenly. Sliding the parchment onto the cookie sheet can be troublesome if your sheets have sides. You can try sliding them onto the backs of the cookie sheet so you don't have to contend with the lip and your nice round macarons deforming.
That said, I have probably 30 sheet pans - they can be purchased pretty inexpensively at a restaurant supply shop (1/2 sheet pans unless your oven is HUGE). I got mine on sale for something like $6/ea. And I use them all the time, not just for cooking - so money well spent in my opinion.
Ha, I am able to rap the hot baking sheets... wearing oven mitts. People would probably get a kick out of watching me try to make a batch of macs...
I never even thought about cooking on the underside of the baking sheet. That's a great suggestion!
Is leaving the batter in the bag really a bad thing? Is it worse than leaving it in the bowl?
Thanks for the suggestions! I think I'll just stock up on baking sheets...