Leah tried a hack using the RMS Un Cover Up Concealer in the shade N11 to create a full coverage foundation by adding a facial oil. She initially didn't use enough product but added more and spread it with a flat brush. To blend it seamlessly, she used a beauty sponge. Leah was impressed with the finish, finding it natural and seamless. The Un Cover Up Concealer by RMS Beauty seems to be a versatile product that can be transformed into a foundation with the addition of facial oil. It provides full coverage and a seamless finish, making it a great option for those looking for a natural look.