1. In a large shallow bowl, whisk together the eggs, milk, sugar, the 1/4 cup of maple syrup, the vanilla and the cinnamon until the sugar is dissolved.
2. Soak the bread slices in the egg mixture, 1 slice at a time, for about 1 minute, then transfer to a tray or baking sheet but don't over soak or the bread will fall apart.
3. Melt 2 tablespoons of the butter in each of 2 large heavy frying pans. Add the bread to the frying pans and cook over moderately low heat, turning once, until golden brown, about 5 minutes per side; if the pans are dry when you turn the toast, swirl in a little more butter. Transfer the French toast to plates, dust with the confectioner’s sugar and serve at once with the warm maple syrup