Lay the bacon out onto one of the parchment lined sheets and place in a cold oven. Set the oven to 450ºF and, once the oven is heated, set a timer for 8 minutes. Check the bacon for crispness. If golden and crisp, remove from the oven and transfer the bacon to a piece of paper towel to cool. If the bacon is still a bit undercooked, continue to cook, checking every 2 minutes or so.
In a large bowl, whisk together the flour, baking powder, baking soda, and salt. Cut the butter into pats and toss with the flour mixture. Using your fingers, snap and rub the butter in until the pieces are about the size of peas. Chop the bacon, add to the mixture along with the cheese and chives, and toss to combine.
Make a well in the centre, pour in 1 ¼ cups of the buttermilk, and stir to combine. The dough should hold together but still be a bit crumbly. If needed, add in another splash of buttermilk.
Lightly flour a work surface and scoop handfuls of the dough out, stacking into a rough tower. Scatter the top with flour and press down to about 1-inch thick. Fold the dough over onto itself and repeat this pressing and folding two to three more times to build flakey layers.
Using a 3-inch round cutter, punch out as many biscuits as possible, pressing straight down through the dough. Gather up any remaining dough and cut out more biscuits. Any scraps left after this second cut can just be baked as is as gathering them again will make for tough biscuits. Transfer the biscuits to the second parchment lined sheet.
Place the biscuits into the freezer for about 10 minutes to chill.
Brush the tops with melted butter and bake for 14 to18 minutes or until risen and golden brown.
Allow the biscuits to cool slightly and serve warm with lots of butter.
