Prepare a batch of hot coals in a chimney or fire by burning them until they turn white. You'll need about 30 coals.
In a large bowl, whisk together the flour, baking soda, garlic powder, parsley flakes, and cayenne.
Add the cubed butter and use a pastry blender or two knifes to blend the butter into the flour until it is pea-sized.
Pour in the milk and stir just until the dry ingredients are fully moistened.
Fold in the Cheddar cheese.
Line a cast iron Dutch oven with parchment paper. Divide the dough into six pieces and place them inside the Dutch oven. Cover with the lid.
Arrange 10 hot coals in the fire pit and set the Dutch oven on top. Place 20 coals on the lid. Cook until the biscuits are fluffy and tender, and the cheese is melted, 15 to 20 minutes. The cooking time will be dependent on the heat of your coals and the outdoor conditions. It may take longer if it's a cool or windy day.
Remove the biscuits and serve immediately.
Notes
Get ahead--Mix your dry ingredients in a resealable plastic bag before heading out on your camping trip.
Don't use your fingers--I don't recommend using your fingers to mix the butter into the flour. It gets too warm and the biscuits will end up gummy.
Make life easier--Line your Dutch oven with parchment. It will make it easier to clean and easier to lift the biscuits out of the hot Dutch oven.
Serve warm--They're best enjoyed warm and served immediately after making.