Add the bacon to a cold, non-stick pan and turn the heat on medium high. As the pan heats the bacon fat will melt, stir until it has browned and crisped evenly all over. Drain on paper towel while you prepare the remaining ingredients.
Place the flour, baking powder, salt, butter and 30 grams of cheddar cheese into a large mixing bowl. Rub together with your hands until the mixture resembles coarse breadcrumbs.
Add the soured cream, bacon, spring onions, chilli and 2 tbsp of the milk. Stir well, adding more milk to make a soft dough.
Turn out onto a lightly floured surface and knead for 30 seconds until smooth. Roll out 1 inch thick and cut into circles with a 2.5 inch fluted biscuit cutter.
Glaze with the beaten egg and sprinkle a little grated mature cheddar on the top of each scone.
Bake in the centre of the oven for 12-15 minutes, until golden. Transfer to a wire rack to cool completely.
Food waste prevention tip: freeze leftover bacon. You can chop it into pieces and cook from frozen when needed.