Slice off the ends of the brioche loaf and cut into 8 thick slices, about 1 1/2 inches thick. Using a knife, cut a small pocket into the side of each piece of bread, taking care not to cut through the remaining three sides.
In small bowl, combine pumpkin puree, brown sugar, pecans, and one teaspoon of the pumpkin pie spice.
Using your fingers, open up the pocket and stuff it with a spoonful of the pumpkin mixture along with a piece of cream cheese. If needed, break the cream cheese up into smaller pieces to ensure even melting. Push filling in far enough so that pocket closes.
In a shallow disk, whisk together eggs, milk, vanilla, and remaining pumpkin pie spice. Ensure that the mixture is well mixed so that the french toast doesn't have obvious pieces of egg on the outside when cooked.
Preheat griddle over medium low heat and grease with butter.
Soak both sides of slices thoroughly in the egg mixture. Lift out of custard and allow excess to drip off before transferring to hot griddle. Cook until golden brown on bottom, about 5-10 minutes, then flip to cook remaining side, taking care not to flatten french toast with spatula.
Serve hot with warm maple syrup and whipped cream.