Begin by placing flour and salt into a large bowl and make a well in the center for the yeast mixture. Cream your yeast with your warm water until fully incorporated and pour into your flour well. Sprinkle some flour from the bowl on top of yeast mixture and allow to sit until bubbles start to foam, around 30 minutes depending on the temperature of your kitchen. Prepare your butter at this point.
Add your melted butter to the flour well as well and begin kneading. You can either knead by hand for up to 10 minutes or knead with a mixer. I chose to knead the dough using my Cuisinart mixture so I cut the time in half. Make sure the dough is fully incorporated and smooth. Mine was pulling away from the sides and was tacky to the touch. Once your dough is fully kneaded, place in an oiled bowl and let rise one hour or until doubled in bulk. I like to use a bowl scraper to scrape out the dough, oil that same bowl and place the dough back into the bowl to be able to work cleaner and more efficiently. Of course if the dough was wetter I would probably use an additional bowl for this step.
While the dough is rising prepare your baking sheet by spraying with nonstick cooking spray. Once your dough has doubled in size, knock it back and shape it into an oval and place it on your prepared baking sheet. Cover and let rise for another 30-40 minutes. It should be pretty large when it is ready to bake. At this point, preheat your oven to 425 F.
Once your oven is heated and your bread is ready to be baked, mix together your egg white, a couple tablespoons of water and salt. Use a pastry brush to brush your bread down with egg wash and then to finish it off sprinkle some whole fennel seeds over the top. You can either leave it as is at this point or take a very sharp knife and cut a deep slash down the middle of the loaf with a quick stroke. I still have trouble getting the cuts right on my bread but practice makes perfect so don't get discouraged! Place your loaf in the oven at 425 F for 20 minutes and then turn down the temperature to 350 F and bake for another 10 minutes. Pull from oven and allow to cool on a wire rack. Enjoy!