How to Make It
Preheat oven to 170°F. Whisk together eggs, ginger, cinnamon, allspice, cloves, nutmeg, and salt in a large bowl until smooth. Stir in cream and milk.
Heat 1 1/2 tablespoons of the butter in a large skillet over medium until foamy. Add 3 bread slices to custard at a time, and let stand until soaked through but not soggy, 30 seconds to 1 minute. Add soaked bread to hot skillet. Cook until golden brown, 2 to 3 minutes per side. Transfer to a sheet pan, and keep warm in oven. Repeat with remaining butter, bread, and custard (re-whisk custard between each batch as spices will settle).
Serve with maple syrup, and dust with powdered sugar.