Step 1: Slice the Challah or brioche bread into thick, 1-inch slices. Set aside.
Step 2: In a shallow dish or pie plate, whisk together the half-n-half (or heavy cream), large eggs, granulated sugar, vanilla extract, and ground cinnamon until well combined and smooth.
Step 3: Heat a large non-stick skillet or griddle over medium heat and add about 1 tablespoon of salted butter.
Step 4: Dip each slice of bread into the egg mixture, ensuring both sides are fully coated but not overly saturated (avoid letting it soak too long, especially if using fresh bread).
Step 5: Place the coated bread slices onto the hot, buttered skillet. Cook for 2-3 minutes per side, or until golden brown and cooked through. Add more butter to the pan as needed for subsequent batches.
Step 6: Serve immediately with your favorite toppings such as maple syrup, fresh berries, powdered sugar, or whipped cream.