Preheat oven to 325 degrees F. Put a pot or kettle of boiling water on the stove.
With a whisk, lightly beat egg yolks and ⅓ cup sugar in a medium bowl by hand just until combined. Do not use an electric mixer, and do not overbeat or your mixture can break. Bring cream and orange zest to a low simmer in a small saucepan over medium-high heat, but do not let it boil. Let it simmer on a very low heat for about 10 minutes to allow the zest to infuse the cream. Gradually stream it into the yolk sugar mixture, while making sure to continually and gently whisk so the yolks do not curdle. Mix just until fully combined and smooth. Do not over-beat, or the mixture will get frothy. Strain it through a fine sieve to catch the zest and to make sure there are no pieces of curdled egg. Evenly divide the custard mixture into two 7-ounce ramekins, making sure not to fill them completely.
Place the ramekins in a baking dish and carefully pour boiling water into the dish to come halfway up the sides of the ramekins. Do not let the water slosh into the ramekins. Bake for about 30 minutes, or just until the custards are set, but slightly wiggly in the center when gently shaken. It will set more as it cools. Remove the custards from the water bath, cool completely at room temperature, about 45 minutes, then refrigerate until firm, about 2 hours, or up to overnight. Cover with plastic wrap if refrigerating overnight.
To serve, spread ½ tablespoon of sugar evenly on the top of each ramekin, then move the ramekin around to make sure the sugar coats the entire surface area. Dump out the excess, so you’re just left with a thin layer of sugar. Heat with a kitchen blowtorch until the sugar caramelizes evenly. Allow to sit at room temperature for a minute or two until the caramelized sugar hardens. When it’s cool to the touch, top with a dollop of ginger whipped cream and a strip of candied orange zest.