In a medium bowl, whisk the yolks, 3 Tbs. of the sugar, the vanilla, and salt until smooth. Add the chopped chocolate to another medium bowl, and set a hand-held fine-mesh strainer on top. Add the cream, milk, orange peel, and 1 Tbs. of the ginger to a medium saucepan, and heat over medium until the mixture reaches a steady simmer and small bubbles form around the sides, about 5 minutes.
Immediately begin slowly pouring the milk mixture into the bowl with the yolks, whisking constantly. Then pour this hot milk-egg mix into the strainer set over the bowl with the chocolate. Discard the solids in the strainer. Whisk the hot milk-egg-chocolate mixture extremely well until smooth.
Pour the chocolate mixture into four 6-oz. ramekins (or heatproof white coffee cups) so they’re three-quarters full. Cover each one with heavy-duty aluminum foil. (If you have to cook the puddings in two batches, store two, covered, in the refrigerator until ready to cook them.) Bring water to a boil in a kettle. Place two of the ramekins in the slow cooker and carefully pour hot water around them to come halfway up their sides. Cover the slow cooker and cook on high until the puddings are cooked through and set so that they only jiggle a tiny bit in their centers, about 1-1⁄2 hours.
Use tongs to carefully remove the hot ramekins from the slow cooker, uncover them, and let sit at room temperature for about 15 minutes. Cover with plastic wrap and chill in the refrigerator until very cold, several hours. Repeat the process if you have to cook the puddings in two batches.
Meanwhile, add the remaining 3 Tbs. sugar, the remaining 1 Tbs. ginger, the strawberries, and orange liqueur to a medium bowl. Mix gently, cover with plastic wrap, and let chill in the fridge for an hour or two.
To serve, top each pudding with a heaping spoonful of the strawberries.