How do we mix the dough? By a wooden spoon or a stand mixer?

The method for making the dough isn't that critical. It is a little stickier dough than most regular bread dough though, and I used a stand mixer with hook as well. When you make bread of any sort, it's hard to give a specific, carved in stone measure for the flour though. If it's particularly humid where you are, or if your flour happens to not be quite as bone dry sometimes- it can simply require a bit more flour to reach the proper consistency of the dough. That's what it sounds like happened in your case. It's easy to fix- simply knead in more flour, tablespoon at a time, until you get a sticky dough to form a ball on the hook. It doesn't even have to stay in a ball shape when you stop the mixer, though it shouldn't disappear into a batter completely. After the first rise, there will be enough gluten to help get it into a rougher ball to finish the rest of the recipe. Then you will need a lot of flour, more than you'd normally use to shape dough in. It's just a sticky situation, but boy the bread is good!