Prep: Set the ramekins, baking sheet, and plastic wrap off to one side. You will want to move quickly once the creme brûlée mixture has thickened.
Whisk: Add the soy milk and cornstarch to a small bowl or measuring cup and whisk vigorously until the cornstarch is fully dissolved.
Make the Cream: Place a medium sauté pan or pot over a burner, but do not turn the burner on yet. Add the soy milk mixture, whipping cream, sugar, vanilla, and salt to the pan and mix well. Turn the heat on to medium, whisking occasionally to ensure there are no clumps in the cornstarch.
Simmer: Begin the whisk the mixture constantly once it begins to steam; continue to cook it for an additional 5 to 7 minutes, until the mixture has thickened and coats the back of a spoon.
Fill the Ramekins: Immediately divide the mixture between the 4 ramekins. Use a spatula to smooth the top of the crème brûlée on each ramekin, but keep in mind that the sugar will cover it later so it doesn’t need to be perfect. Place each filled ramekin on the baking sheet.
Cover: Cut a large sheet of plastic wrap and place it gently over the baking sheet. Press the plastic wrap over the top of each ramekin so it completely covers the crème brûlée filling, then secure it to the edges of the baking tray. You can also cut 4 individual squares of plastic wrap, but I prefer to use one larger sheet as it is less finicky.
Chill: Place the baking sheet in the refrigerator and let it sit for at least 3 hours, until chilled and set. You can store the covered crème brûlée for up to 2 days covered like this.
Brûlée: Remove the ramekins from the fridge and discard the plastic wrap. Working one ramekin at a time, sprinkle the top of the crème brûlée with 1 to 2 tablespoons of sugar, rotating the ramekin so every portion of the top is covered with a layer of sugar. Use a culinary torch to brûlée the sugar until it is bubbling and golden brown. I find it best to continuously move the torch in small circles, working on browning small sections of the ramekin at a time before moving on to the next area. Repeat with the remaining ramekins.
Serve: Let the ramekin sit for at least 5 minutes, to allow the sugar to cool slightly and harden. Serve immediately after.