Preheat your oven to 375°F (190°C) and line a baking sheet with parchment paper.

In a pot of boiling water, add the peeled and cubed sweet potatoes and cook until tender, about 15 minutes. Mash and let cool.

In a large bowl, whisk together the eggs, milk, cinnamon, nutmeg, and a pinch of salt. Stir in the cooled mashed sweet potatoes.

Gently dip slices of bread in the sweet potato mixture, ensuring they are soaked but not soggy.

Arrange soaked bread on the prepared baking sheet and bake for about 25 minutes, flipping halfway through.

Prepare the pecan crumble by combining chopped pecans, brown sugar, and melted butter; sprinkle over French toast during the last 5 minutes of baking.

Once out of the oven, drizzle warm maple syrup over the French toast and add extra pecan crumble if desired.