I have worked at McD's. The secret to the egg shape is the egg cooker thingie McD's have. It sorta reminds me of a 6-pack plastic soda holder..only the egg cooker has thicker bands and is made of teflon coated metal. You put the egg cooker on the grill, swab some of the (sickening, blech !) grease/lard/Oleo on the parts, crack an egg into it..( real eggs btw)...put a metal flat "lid" over it,the lid has a small funnel on top..you pour water in the funnel and I suppose it dribbles down over the cooking eggs..Next, set the timer..and it cooks from the heat of the grill. I believe these 6 pack cooker things are custom made for McD's..so you cannot buy them in a store. The fluffy size is probably from the steam of the water.

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