To make biscuits
Preheat the oven to 450°F.
Prepare 9-inch straight sided cake pan with butter and set aside.
In large bowl, whisk together flour, baking powder and kosher salt. Add small pieces of butter and work into flour mixture with fingers until texture resembles coarse crumbs.
Stir buttermilk into flour mixture until it just comes together and dough is a little shaggy looking. Knead dough a few times in bowl then turn out onto lightly floured surface. Pat dough into a ½-inch thick shape.
Cut biscuits out with 2-inch biscuit cutter dipped in flour. Place biscuits in the prepared pan. Fold remaining dough over itself and pat into another ½-inch thick shape and continue to cut biscuits until you’ve used all the dough. You should have about 12 biscuits.
Bake 15 minutes or until biscuits are golden brown. Remove from oven and turn out into towel, cover and let rest while preparing sandwiches.
To prepare sandwiches
Separate warm biscuits into top and bottom halves and place 1 slice of Cheddar cheese on the bottom, top with 4-5 slices of hard-boiled egg, a few slices of bacon and top biscuit half.
Repeat with remaining biscuits.
If biscuits have cooled and cheese doesn’t melt, place composed sandwiches on plate and place in turned off but still warm oven for 5 minutes or so for cheese to melt. Or, microwave on high for 30 seconds.