In a large mixing bowl, whisk together the flour, instant yeast, and salt until evenly combined.
Add the warm water to the dry ingredients and stir with a wooden spoon or spatula until a shaggy dough forms and all flour is hydrated.
Fold in the dried cranberries and chopped walnuts until evenly distributed throughout the dough.
Cover the bowl tightly with plastic wrap or a clean kitchen towel and let it rest at room temperature for 12 hours, or overnight, until the surface is bubbly and the dough has risen.
After the dough has risen, generously flour a clean work surface and your hands. Turn the dough out onto the floured surface.
With floured hands, gently fold the dough over itself once or twice to shape it into a rough ball. Do not knead.
Place the dough seam side down on a large piece of parchment paper. Cover loosely with a kitchen towel and let it rest for 30 minutes while you preheat the oven.
About 30 minutes before baking, place a Dutch oven (or heavy oven-safe pot with lid) inside the oven and preheat to 450°F (230°C).
Carefully remove the hot Dutch oven from the oven. Using the parchment paper, lift the dough and place it into the Dutch oven.
Cover with the lid and bake for 30 minutes.
Remove the lid and bake for an additional 15 minutes, or until the bread is deep golden brown and crusty.
Carefully remove the bread from the Dutch oven and transfer to a wire rack to cool completely before slicing.