Preheat the oven to 425 degrees with the rack in the center. Line a sheet pan or cookie sheet with parchment or a silicone mat.
Cook your four pieces of bacon first so they can cool off before you chop them and add them into the batter. I just microwaved mine but however you like to cook your bacon is fine - pan, broil, microwave.
In a medium sized bowl, whisk together the flour, baking powder, baking soda, sugar, and salt.
In medium size liquid measuring cup or bowl, whisk together the yogurt and milk. I put the yogurt into a measuring cup, then poured the milk right on top - the yogurt is thick enough to stay put and it saves me a dish or two.
Finely chop the bacon. (don't go crazy here - a little texture is ok).
Grate the two tablespoons of frozen butter, directly into the flour mixture if you want. Use a whisk or fork to combine it into the flour mixture, then add the cheddar and bacon pieces and be sure the mixture is well-combined.
Now pour in the yogurt/milk mixture and use a small fork to incorporate and then a spatula to turn the dough over a few times to be sure you have all the flour and liquid combined. Don't over mix but make sure it is thoroughly combined. The dough should be a little moist but not at all runny. If it seems too dry to drop onto a sheet pan, then add a tablespoon or two of milk or buttermilk to moisten it up.
Now let the dough rest for 5 minutes or longer if you have time.
Using an ice cream scoop or large spoon drop a little under a 1/4 cup of dough for each biscuit on to the parchment lined baking sheet. Leave about 1.5 inches between each one so they cook evenly and crisp up. Bake for 10 minutes, then move to a cooling rack. Eat them warm out of the oven if possible but they reheat nicely the next day.