Heat oven to 350°F.
In a small saucepan, whisk together the ingredients for syrup. Simmer for five minutes and set aside.
Prepare orange-scented whipped cream.
Place brioche on a baking sheet and bake for 5 minutes. Flip slices and bake for 4–5 minutes, or until lightly toasted on both sides.
While brioche is toasting, combine custard ingredients in a wide bowl. Whisk until well combined.
Heat a skillet on medium heat. Add one teaspoon of butter to the skillet. Dip 3–4 brioche slices in custard, then place in pan. Cook for 2–3 minutes or until lightly browned.
Add another teaspoon of butter, flip the toast, and cook for 2–3 more minutes. Sprinkle the top-facing side with 1/4 teaspoon cinnamon sugar. Flip and cook for 15–30 seconds. Remove from pan.
To serve, place cinnamon sugar side face up on a plate. Top with orange-scented whipped cream, syrup, and dust with powdered sugar.