Is there supposed to be any difference between the lemon filling on either? Also, most lemon bar recipes I've seen call for 4 to 8 complete eggs (yolks with whites), and one or two recipes are using just the egg yolks. Is one better than the other, at least in terms of yellowness to the filling? The guy from kitchen conundrums says the yolks give richness and creaminess to the mixture while the white gives structure.\n\nAlso, I made some lemon bars today, I followed Chef John's recipe from Food Wishes. Now he only used two eggs and one yolk. Mine came out very tasty, though actually could do with less sugar than he puts in, they're incredibly sweet. But mine barely had any yellowness to them and yet they look quite yellow in his video. My mixture had a pale yellow colour when it was first poured over the pastry which I'd blind baked, but when it came out of the oven and I sliced it up, the colour was very translucent, more apple filling coloured than yellow.\n\nI can only guess that more eggs would give that yellow, but would it need to be all yolks only to concentrate the colour or would that not matter? I want it to look really vibrant. Mine looked bland, more like pizza. :D\n\nFinally, I'd dredge the tops of some of the bars with icing sugar, but I also want to put some meringue topping on some others. I know how to whip up whites and get stiff peaks, and I have a blowtorch lighter that I can use to toast it for that golden brown colour. In Chef John's video, he shows whipping the whites, putting it on the bars and lightly torching it.\n\nBut don't you need to preheat the whites to 160F before whipping to kill off any possibility of salmonella? I don't know how safe it is to eat meringue without doing that? I don't mind spending a few minutes heating the whites. I've got one of those infrared thermometer guns which has proven quite useful. Would that be ok to point at the heated egg whites rather than buying a candy thermometer?