Cath's kitchen is basic, utilitarian, and plain. The fittings themselves provide a blank canvas which can be accessorised any way she chooses - instead of being a slave to fashion, she can adapt her kitchen to suit her own style.
You can easily copy this approach by choosing a kitchen that is classic but also quite plain. Keep styling on the doors low key, choose tiles or a splashback material that's neutral and go for flooring that's good quality, but understated. Then, swap in different accessories to dress the kitchen as the mood takes you - brights for a fun dinner party, neutrals for everyday use.