How to keep aglio olio warm?
If you are referring to the pasta dish, don't make the aglio e olio until you put your pasta in the water.  Then, when pasta is a minute or so from being finished remove it from the water and place it into the pan with the aglio e olio to finish cooking.  Add a little pasta water to emulsify.  Serve. In this scenario, it should never cool during preparation and the entire dish only takes as long to make as the cooking of the pasta.