3/4 cup granulated sugar
1/4 cup cornstarch
2 1/2 cups whole milk
3 extra large egg yolks, lightly beaten
2 tablespoons finely grated lemon zest (or 1 tablespoon lemon zest + 1 tablespoon orange zest)
1/4 teaspoon kosher salt
1/2 cup freshly squeezed Meyer lemon juice (or 1/4 cup freshly squeezed lemon juice + 1/4 cup freshly squeezed orange juice)
2 tablespoons unsalted butter at room temperature
In a medium saucepan, whisk together the sugar and cornstarch. Add the milk, egg yolks, zest, and salt and whisk until smooth. Cook over medium heat, stirring frequently at first and constantly toward the end, until thickened.
Remove the pan from the heat and stir in the citrus juice and butter. Place a fine mesh sieve over a large bowl and pour the mixture through the strainer. Divide the mixture into 6 serving dishes and let cool to room temperature. Refrigerate, loosely covered (tightly covered will trap too much moisture, making a watery pudding) for at least 3 hours and up to 3 days. Serve chilled by itself or with lightly sweetened whipped cream.