In a bowl, combine sliced apples, sugar, cinnamon, lemon juice, and cornstarch. Mix until apples are evenly coated and slightly juicy.
Cut large squares of aluminum foil and lightly grease the center of each piece.
Flatten each biscuit into a round shape and place it in the center of the foil sheet.
Spoon the apple mixture onto the biscuit base, keeping it centered and not overfilled.
Add small cubes of butter evenly over the apple filling.
Fold the foil over the filling and seal all edges tightly to form a secure packet.
Place packets over a campfire or grill and cook for 10 to 15 minutes, turning once halfway through cooking.
For oven method, bake at 375 degrees Fahrenheit for 15 to 20 minutes until apples are soft and biscuit is cooked through.
Remove from heat and let packets rest for a few minutes before carefully opening.
Serve warm directly from the foil or transfer to a plate.