Preheat the oven to 400°F (207°C).
Open the biscuit can and separate the biscuits. Cut the string cheese into 10 pieces. Grease a 10-inch cast-iron skillet with 1 tablespoon of the melted butter.
Wrap the cheese bombs by placing one cube of cheese in the center of each biscuit. Carefully wrap the biscuit dough around the cheese and pinch to seal. Avoid pressing and pinching too hard on the biscuit dough, as this may prevent them from being flaky after baking.
Brush the surface with the remaining melted butter and sprinkle some kosher salt on top.
Bake for 10-15 minutes, or until the surface is golden brown. Serve warm.