In a wide, shallow dish or pie plate, vigorously whisk together the eggs, pumpkin puree, whole milk, maple syrup, pumpkin pie spice, vanilla extract, and sea salt until completely smooth with no egg streaks.

Place a large cast-iron skillet or nonstick griddle over medium heat. Add 1 tablespoon of butter and allow it to melt and foam evenly across the cooking surface.

Dip each slice of brioche into the pumpkin custard mixture, allowing it to soak for about 15 to 20 seconds per side so the bread absorbs the custard without falling apart.

Place soaked slices directly into the hot foaming butter. Cook for 3 to 4 minutes on the first side until deeply golden-brown and caramelized. Flip with a spatula and cook the second side for another 2 to 3 minutes until puffed and cooked through to the center.

Transfer hot French toast to serving plates. Top immediately with a dollop of whipped cinnamon butter, toasted chopped pecans, and a generous drizzle of warm maple syrup. Dust lightly with powdered sugar and enjoy warm.