Adjust oven rack to lower-middle position and heat oven to 300 degrees F.
Combine 2 cups of the cream, the sugar, and salt in medium saucepan; with a paring knife, scrape seeds from vanilla bean into pan, submerge pod in cream, and bring mixture to a boil over medium heat, stirring occasionally to ensure that sugar dissolves. Take pan off heat and let steep 15 minutes to infuse flavors.
Meanwhile, place kitchen towel in bottom of large baking dish or roasting pan and arrange eight 4- to 5-ounce ramekins (or shallow fluted dishes) on towel. Bring kettle or large saucepan of water to boil over high heat.
After cream has steeped, stir in remaining 2 cups cream to cool down mixture. Whisk yolks in large bowl until broken up and combined. Whisk about 1 cup cream mixture into yolks until loosened and combined; repeat with another 1 cup cream. Add remaining cream and whisk until evenly colored and thoroughly combined. Strain through fine-mesh strainer into 2-quart measuring cup or pitcher (or clean medium bowl); discard solids in strainer. Pour or ladle mixture into ramekins, dividing it evenly among them.
Carefully place baking dish with ramekins on oven rack; pour boiling water into dish, taking care not to splash water into ramekins, until water reaches two-thirds height of ramekins. Bake until centers of custards are just barely set and are no longer sloshy and digital instant-read thermometer inserted in centers registers 170 to 175 degrees, 30 to 35 minutes (25 to 30 minutes for shallow fluted dishes). Begin checking temperature about 5 minutes before recommended time.
Transfer ramekins to wire rack; cool to room temperature, about 2 hours. Set ramekins on rimmed baking sheet, cover tightly with plastic wrap, and refrigerate until cold, at least 4 hours or up to 4 days.
Uncover ramekins; if condensation has collected on custards, place paper towel on surface to soak up moisture. Sprinkle each with about 1 teaspoon turbinado sugar (1½ teaspoons for shallow fluted dishes); tilt and tap ramekin for even coverage. Ignite kitchen torch and caramelize sugar. Refrigerate ramekins, uncovered, to re-chill, 30 to 45 minutes (but no longer); serve.
Vanilla Bean: You can also substitute 2 teaspoons of vanilla extract or vanilla bean paste, whisked into the yolks in step 4.
Egg Yolks: Separate the eggs and whisk the yolks after the cream has finished steeping; if let to sit, the surface of the yolks will dry and form a film.
Turbinado Sugar: Also known as raw cane sugar or demerara sugar. You can substitute regular granulated sugar but only use 1 scant teaspoon on each ramekin.
Kitchen Torch Alternative: If you do not have a kitchen torch, you can use your oven's broiler to caramelize the sugar. Be sure that your custard is thoroughly chilled (overnight is best here), then place the ramekins on a baking sheet on a rack directly below the broiler. Keep a very close eye on it so it doesn't burn, as it will only take a minute or so to caramelize.
Ramekin Alternative: Ramekins are truly ideal for this recipe, however, you can substitute a large, wide pan (ceramic is best), just be sure it can still fit in a water bath inside a larger pan and, depending on the size, you may need to adjust the baking time.
Make-Ahead: This crème brûlée recipe can be made up to 4 days in advance. Prepare it through chilling the custard, then proceed with the sugar topping just prior to serving.
Freezing Instructions: Make the recipe as directed, preparing and baking the custard-filled ramekins. Once cooled to room temperature and chilled, cover tightly and freeze for up to 1 month. Thaw in the refrigerator overnight and then proceed with sprinkling with sugar and torching.
Storage: This is best eaten shortly after torching the top, but leftovers can be stored in the refrigerator for up to 2 days.