Take your canned biscuits and cut out the centers of each biscuit using a cookie cutter or small biscuit cutter, even a bottle cap works, Set aside.
Melt your butter in a shallow bowl that is large enough to dip a doughnut into, set aside.
In another shallow bowl, mix in the cinnamon & sugar, set aside.
In a medium frying pan, fill with the vegetable oil, only about half an inch or so
Heat the oil to 350F, if you don't have a cooking thermometer, use one little biscuit center and drop it into the pan, making sure it sizzles when it hits the oil.
Once the oil is ready drop 1-2 doughnuts at a time into the oil, because they cook quickly
When one side is golden brown, flip it over with tongs and when that side is golden remove from oil and place on a paper towel lined pan or plate.