Preheat the oven to 425F. Fill a shallow cake pan with water or ice and put it on the bottom rack, and make sure another rack is in the middle. In a large bowl, whisk together the warm water, yeast, and sugar. Set the bowl on top of your preheating oven for ten minutes. Add half the flour and the salt, then add more flour a half cup at a time until you have a soft dough. Knead it for a few minutes, until it's smooth and elastic. (You can totally do this with the dough hook on your stand mixer, if you have one.)
Cut the dough into four pieces and roll each into a long, thin rope. Twist two together to make two baguettes and set them on a parchment lined baking sheet. Let it sit for another 15-30 minutes on top of your warm oven.
Bake on the middle rack of your oven for 15-20 minutes, until golden and crusty.