Add the spaghetti to a pan of salted boiling water. Cook for approximately 7-8 minutes. The pasta will be finished off with the sauce, so you want it slightly underdone.

Slice the garlic as thin as possible, and fry on a gentle heat. You don't want to really brown these, just slowly cook them. When they start to slightly stick together, remove them from the pan.

Add the bacon lardons, turn up the heat so the fat can render down, and they start to go nice and crispy.

By now your spaghetti should be ready. It should still have a bite, and shouldn't be fully cooked. Save a cup of the pasta water and drain the rest.

Add the garlic back into the pan with the bacon, add the spaghetti, and a glug of the pasta water. Stirring constantly add the grated cheddar and parmesan. If you feel it needs loosening add some more of the pasta water, with the constant stirring the cheese should start to emulsify and form the sauce.

Keep an eye on your pasta, it's easy to overcook it at this stage, I like mine al dente, so try and complete this stage nice and quickly, as it's easy to over do it, and turn your spaghetti into mush.