In a medium saucepan bring 2 cups of water to a boil over medium heat and add the cinnamon, cardamom, ginger, peppercorns and cloves, simmering for 2 minutes. Add the tea bags, milk and sugar, stirring to combine. Remove from heat then cover the pot and let it steep for 10 minutes.
Strain tea into a large mixing bowl, discarding spices and tea bags. Let cool completely to room temperature.
For the French toast:
In the large bowl whisk in the eggs, egg yolks and vanilla extract into the chai.
Heat a large cast iron skillet or non-stick sauté pan over medium heat, add 1 tablespoon of the butter and allow to melt.
Working with one slice of bread at a time, soak the bread in the egg mixture, turning to coat both sides.
Add two slices of the bread and cook until golden brown on the bottom, about 2 minutes. Flip and cook until golden brown on the other side, about 2 minutes. Add an additional tablespoon of butter and repeat with the remaining slices of bread.
Top with whipped cream or maple syrup and serve immediately.
Notes
Make the chai ahead of time and refrigerate it overnight—this deepens the flavor and makes morning prep even easier.