Place the chopped white chocolate in a small, wide sealable container and position a mesh strainer and spatula nearby. Keeping everything ready prevents the hot citrus cream from cooling before it reaches the chocolate.

Heat the unsalted butter and orange zest in a small saucepan over medium heat, whisking as the mixture comes to a boil. Once bubbling, cook for 1 minute and keep whisking so the zest infuses without scorching.

Pour in the heavy whipping cream while whisking, then continue cooking for 1 to 2 minutes. Look for gentle bubbles gathering around the edges rather than a rapid boil, then remove the pan from the heat.

Strain the hot butter and cream mixture over the chopped white chocolate, pressing the zest against the mesh with a spatula. The strained liquid should smell deeply orange while the ganache stays free of gritty zest pieces.

Leave the mixture untouched for 1 minute, then add the orange extract and optional oil-based food coloring before whisking. Stop when the ganache looks glossy and thick; a few tiny pieces of chocolate may remain and will melt as you stir.

Seal the container and place it in the freezer for 1 hour, or until the ganache is firm enough to handle. The mixture should hold its shape when scraped with a spoon instead of flowing back into the container.

Put 1/4 cup powdered sugar into a clean sealable container and the remaining 1/4 cup powdered sugar into a small bowl. Keep damp cloths or paper towels nearby because the filling softens quickly against warm hands.

Scoop about 1 tablespoon of chilled ganache, roll it into a ball, and toss it in the powdered sugar in the bowl. Transfer the coated truffle to the larger container and repeat until all the ganache has been shaped.

Seal the larger container and shake it gently to cover the truffles with the remaining powdered sugar. The extra sugar should settle around each ball, ready to refresh the coating if moisture dulls it later.

Return the sealed container to the freezer for 1 hour, or until the truffles feel firm. The centers should be set enough to lift cleanly without leaving a soft impression.

Serve the truffles as desired. The best texture is cool and creamy, with a delicate powdered sugar finish.