How can I make the tops of my macarons smooth? After a recent trip to France, I have become mildly obsessed with making macarons (using this recipe). I have made a couple of batches so far - the first didn't turn out well, more like cookies than macarons, due to under-whipped egg whites and too-coarse almonds.

The second batch has turned out better, much more like macarons. I whipped the egg whites to stiff, glossy peaks and blitzed the almonds, powdered sugar and cocoa in a food processor to remove lumps and make the almonds finer. Some of the macarons even have the characteristic little 'feet'.

However, while the flavour and texture seem generally good, they don't have the smooth, perfect surface of a proper macaron. Looking at videos online, it would seem my mixture is too stiff, because any little tip of mixture left by the piping bag fails to 'melt' into the main part of the macaron - it simply sits there. Also, any little craters left by air holes in the mixture fail to smooth themselves out, so the result is a bumpy macaron.

Given that the egg whites need to be stiff and glossy, what else could be a factor in achieving a smooth macaron? I assume the amount of powdered sugar is a factor, but how much can I safely reduce the amount by?
The meringue should be glossy and form soft peaks. When you take your whisk out of the meringue it should look like this:





The French say that when you take the whisk out of the meringue, it has to look a bit like a bird's beak, hence the way the meringue forms a soft peak slightly pointing downwards.

But to be honest, I don't believe that is you problem. I guess you just undermix your batter. People often say it has to fall like a ribbon or like magma, but I always thought that is hard to imagine. You can take a knife and cut through the batter. If it flows back immediately, it's ready. But let me tell you: One or two strokes too much with the spatula and the batter becomes unusable.

And one tip I can give you: The process of transferring the batter into the piping bag also 'mixes' the batter, so maybe don't go too far if you are unsure.

And as already said, it is important to tap the the tray from the bottom after piping as it helps to remove any air bubbles in there. Also, always pipe straight from the top (90° angle). This also helps the batter to smooth out.

I wouldn't recommend you to chance the amount of powdered sugar, as the French use Tant pour Tant (TPT) for their macarons, which means fine almond meal and powdered sugar are mixed proportional to each other.

When mixed perfect, it looks like this:

http://1.bp.blogspot.com/_WhPHUKwckUw/S4WP1eBE7pI/AAAAAAAAB00/gYqFjGOvEiU/s1600-h/5.jpg 

When gone too far, it looks like this:

http://3.bp.blogspot.com/_WhPHUKwckUw/S4WP-q8RrdI/AAAAAAAAB08/7R6uO1uGfBQ/s1600-h/6.jpg 

Maybe try counting your strokes while mixing, some people say that it helped them.