In a large, shallow bowl, whisk together the pumpkin puree and eggs until completely smooth. The texture should be velvety without any egg streaks.
Add the milk, heavy cream, brown sugar, vanilla extract, and all spices. Whisk vigorously until everything is fully incorporated and the batter has a consistent orange-amber color.
Allow your batter to rest for 5 minutes to improve flavor infusion.
If using fresh bread, consider leaving it out uncovered for 1-2 hours before making French toast. Slightly stale bread absorbs the batter better without becoming soggy.
Place each slice of bread in the pumpkin batter, allowing it to soak for 20-30 seconds per side. The bread should absorb enough batter to become saturated but not so much that it falls apart.
Heat a large skillet or griddle over medium heat and melt 1 tablespoon of butter. Once the butter is bubbling (but not browning), add 2-3 slices of soaked bread.
Cook for 3-4 minutes on each side until golden brown and slightly crisp at the edges, while remaining soft in the center.
Transfer cooked slices to a baking sheet and keep warm in a 200°F oven while you prepare the remaining batch.
Add more butter to the pan as needed between batches to maintain that beautiful golden color and prevent sticking.
Serve with maple syrup and your choice of toppings like whipped cream, chopped nuts, fresh berries, or a sprinkle of cinnamon.