In a large mixing bowl, whisk together the flour, instant yeast, and salt until evenly combined.
Add the warm water and maple syrup to the dry ingredients. Stir with a wooden spoon or spatula until a sticky dough forms and all the flour is incorporated.
Fold in the toasted and chopped pecans until evenly distributed throughout the dough.
Cover the bowl with plastic wrap or a clean kitchen towel and let the dough rise at room temperature for 12 to 16 hours, until it is bubbly and has doubled in size.
When ready to bake, place a 5 to 6-quart Dutch oven with its lid inside your oven and preheat to 450°F (232°C) for at least 30 minutes.
While the oven and Dutch oven are heating, lightly flour a clean work surface and gently turn the dough out onto it. Shape the dough into a round loaf by folding the edges toward the center. Let it rest for 15 minutes.
Using a piece of parchment paper, carefully transfer the dough into the hot Dutch oven. Cover with the lid and bake for 30 minutes.
Remove the lid and bake for an additional 10 minutes, until the crust is deep golden brown and crisp.
Carefully remove the bread from the Dutch oven and transfer it to a wire rack. Let cool completely before slicing.