Those of us who bake cookies probably have a good mixer with a sturdy engine. Many of us have KitchenAid mixers. The KitchenAid comes in three different models, the Classic (small) the Artisan (medium) and the Professional (macDaddy).There is something to love about all three and which one you want is probably attributed to how much time you spend baking. I have owned all three so people often ask me which one I like best. My personal preference is the mid-range mixer, the Artisan, because after its strength and power, my favorite thing about it is that the head tilts back. All three models come with a paddle, a dough hook and a whisk attachment.
If you have the macDaddy, you can stop reading. The Classic and Artisan have smaller engines in them, so sometimes when you are mixing the thick cookie dough, the engine struggles. You can hear it whine as the ingredients incorporate. It might whine and struggle, but it still gets the job done.
Recently one of The Cookie School instructors told me that when she began to mix her dough, the engine started bellowing smoke! That's NOT GOOD. She told me that she changed from the paddle to the dough hook and while it took longer to mix, it worked like a charm. No struggling. No smoke.
That sounded like great advice to me so I tried it myself. My own mixer that typically struggles when mixing the thick dough seemed to be a piece of cake for the dough hook. I have made bread dough with that before but always used the paddle for cookie dough. Compare the way the mixer mixes the ingredients with each attachment.
Paddle
Dough Hook
Use whichever one you like (or for some, whichever one you can FIND), but I am doing more and more with my dough hook lately. I am convinced it is better for my engine.