In a large mixing bowl, whisk together the flour, instant yeast, and salt.
Add the warm water and maple syrup to the dry ingredients and stir with a wooden spoon or spatula until a shaggy dough forms and all flour is incorporated.
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 rest at room temperature for 12 to 16 hours, until it is bubbly and has doubled in size.
After the dough has risen, generously flour a work surface and your hands. Turn the dough out onto the floured surface and fold it 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 it loosely with a kitchen towel and let it rest for 1 to 2 hours, until it has risen and looks puffy.
About 30 minutes before baking, place a Dutch oven with its lid in the oven and preheat to 450°F (232°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.
Carefully remove the bread from the Dutch oven and transfer it to a wire rack to cool completely before slicing.