In a large bowl, mix the flour, sea salt, rosemary, and yeast together. Mix in the water and use a spatula to blend until well combined.
3 cups all-purpose flour, 1¾ teaspoons sea salt, ¾ cup fresh rosemary leaves, ½ teaspoon active dry yeast, 1½ cups water
Cover the bowl with plastic wrap or a clean, damp dish towel and allow it to sit on the counter overnight, at least 12 hours. (patience is a virtue!)
Preheat oven to 450°F degrees with a Dutch oven inside.
Once preheated, carefully remove the Dutch oven from the hot oven and remove the lid from it. Use oven mitts!
Flour a clean work surface as well as your hands. Remove the dough from the bowl and form it into a ball. This is a no-knead recipe, but you may have to fold it a couple of times to get it to form the shape you want. Place the dough into the bottom of the Dutch Oven (be careful not to burn your hands; the cast iron will be HOT!)
Bake for 30 minutes with the lid on, then remove the lid and bake another 15-20 minutes, until the bread is golden brown.
Remove from the oven and allow to cool. Cut and serve! Perfect compliment for soups!