In a large mixing bowl, combine all the custard ingredients: eggs, milk, sugar, extracts, salt and spices. Use a hand whisk to whisk everything together for a few minutes, until the custard is creamy and smooth.
Preheat a frying pan or two over medium-low heat. Add 1 1/2 to 2 tablespoons butter per pan and allow the butter to melt. Meanwhile, slice the brioche bread if not pre-sliced. Dip each slice into the custard and let it soak in the custard very well. Allow any excess to drip back into the pan, then place the slice onto the preheat pan.
Fry the French toast in batches of 2 or 3, depending on pan size. Fry low and slow for 3 to 4 minutes per side, turning when the sugar has caramelized and the bread is golden brown. Remove the finished toast onto a tray and keep warm. Repeat the same process for the remaining toast, adding more butter for each new batch.
Serve warm with whipped cream (recipe above in post), maple syrup, berries and a sprinkle of powdered sugar, if desired.