Heat large skillet or griddle over medium heat for 5 minutes.
Meanwhile, in a casserole dish or other shallow, wide dish, beat eggs with milk, pumpkin puree, bourbon, vanilla extract, brown sugar, and cinnamon.
Soak bread without oversaturating, about 30-40 seconds per side. Pick up bread and allow excess batter to drip off; repeat with remaining slices.
Optional: Melt 1 tablespoon butter in hot skillet or griddle.
Add prepared bread to skillet without overcrowding. Cook until golden brown, about 1 minute 45 seconds on first side and 1 minute on the second. Serve immediately.