Split the vanilla bean, scrape out seeds, and place the seeds and pod into to a small sauce pan with the half-and-half. Warm gently until it almost comes to a simmer, stir, then turn off the heat and let stand for 30 minutes.
Slice the pears. Melt 2 tablespoons butter in a skillet and sauté the pears on medium heat until lightly golden (about 10 to12 minutes). Add 1 tablespoon maple syrup and simmer a few more minutes until nicely caramelized. Set aside.
Cut the bread in to 1/2-inch slices. In a medium bowl, beat the eggs, salt, spices, orange zest, and another 3 tablespoons maple syrup. When the half-and-half has cooled, remove the vanilla pod and add the milk a little at a time to the egg mixture, mixing until combined. (Do NOT add hot cream to the egg mixture or else the eggs will curdle. Either let the cream cool or temper the eggs by adding just a little warm cream at a time, mixing in between each addition.)
Heat the oven to 350° F and generously butter a baking dish. Layer the bread, hazelnuts, and caramelized pears in the dish and pour all of the buttery syrup from the pan evenly over the bread. Pour the batter over everything, using a spatula to ensure that it goes in all the cracks crevasses. Let sit at least 30 minutes so the bread can soak up the batter, or refrigerate overnight. Right before placing it in the oven, drizzle the top with 1 more tablespoon maple syrup and sprinkle with a pinch of cardamon. Bake 45 to 50 minutes until puffed and golden. If your layers measure higher than two inches, you may need to bake longer. Check the middle to see if all the liquid is cooked. I have found that when it puffs up, it's usually done. Melt small dots butter over the top and serve with warm maple syrup.