Heat a large cast-iron skillet over medium heat. Add the brown sugar, butter and 1 tablespoon water. Cook, stirring, until the sugar is dissolved and the mixture is bubbling. Add the apples, vanilla, salt, cinnamon and lemon juice. Mix together the cornstarch and 1 tablespoon water in a small bowl to create a slurry. Add the cornstarch mixture to the skillet and stir to combine. Cook, stirring occasionally, until the apples are tender, about 5 minutes. Pour into a heatproof bowl and let cool completely. You can make this ahead of time and chill in the fridge a day or so in advance if needed.
To make the pies, roll each biscuit into about a 5-inch circle that is about 1/8 inch thick. Spoon 2 generous tablespoons of the apple filling on each round of dough, just off center. Use your finger and run a little water around the edges to help them seal completely. Fold one half of each circle over onto the other half and seal in the apple filling, forcing out any air that you can. Press the edges together and crimp with a fork. Continue until they're all assembled.
Heat the oil in a high-sided skillet over medium heat until it reaches 350 degrees F. Fry the pies 2 or 3 at a time for about 5 minutes, carefully turning them halfway through. Remove them to a paper towel-lined baking sheet to drain.
When all the pies are fried, sift the confectioners' sugar over top. Serve with Cinnamon-Caramel Sauce or store-bought caramel sauce.
Yield:1 1/2 cups
Mix the brown sugar, half-and-half, butter and a pinch of salt in a saucepan over medium-low heat. Cook, whisking gently, until it thickens, 2 to 3 minutes. Whisk in the vanilla, cinnamon and a second pinch of salt and cook another minute to thicken further. Turn off the heat and allow to cool to room temperature before serving. Chill if not using immediately.