In a large mixing bowl, whisk together the flour, instant yeast, and salt until well combined.
Add the warm water and maple syrup to the dry ingredients. Stir with a wooden spoon or spatula until a shaggy dough forms.
Fold in the toasted and chopped pecans until evenly distributed throughout the dough.
Cover the bowl tightly with plastic wrap or a clean kitchen towel and let the dough rise at room temperature for 12 to 16 hours, until the surface is dotted with bubbles and the dough has doubled in size.
Lightly flour a clean work surface and turn the dough out onto it. With floured hands, gently shape the dough into a round loaf by folding the edges toward the center.
Place the dough seam side down on a piece of parchment paper. Cover with a kitchen towel and let it rest for 30 minutes.
About 30 minutes before baking, place a Dutch oven with its lid in 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, until the bread is deep golden brown and crusty.
Remove the bread from the Dutch oven and transfer to a wire rack. Let cool completely before slicing.