In a saucepan, rub the orange zest into the sugar with your fingers. Add the salt and corn starch, and whisk together to combine.
Gradually whisk in a small amount of the milk to form a smooth slurry, then whisk in the rest of the milk and the cream.
Separate the eggs (saving the whites for another use), and place the yolks in a bowl.
Set the saucepan over medium heat. Warm the milk mixture until it starts to steam. Slowly add 1 cup of the hot milk mixture to the egg yolks, whisking the yolks to temper them with the hot liquid. Now scrape the warmed yolks and milk back into the saucepan.Continue to cook the custard, whisking constantly, until the custard starts to bubble and thicken, then cook for 1 full minute.
Remove the pan from the heat, and whisk the vnlla Vanilla Extract + Orange (or vanilla and orange extracts) and the butter into the custard until smooth.
Pour the custard through a mesh strainer into a bowl to strain out the orange zest and any bits of cooked egg. This step is optional, but straining makes a perfectly smooth custard.
Cover the bowl with plastic wrap resting right against the surface of the custard, and refrigerate until cool and thick, about 2-3 hours, or overnight.
Stir the chilled custard to loosen it up a bit, then spoon into serving dishes. Grate some fresh orange zest on top, and sprinkle with vanilla powder.
Notes
You can make this custard up to 3 days in advance, keeping it tightly covered.
Serve the custard in ramekins, layer with cake, fruit and whipped cream for a trifle, use as a filling in an icebox cake, or serve on the side with warm fruit crumble or pie instead of ice cream.
Be sure to visit the vnlla Extract Co. store on Amazon, to shop their complete line of vanilla extracts.