Greasy Grandma World is another dimension that Rick and Morty pass through quickly while pursued by the Council of Ricks in Close Rick-counters of the Rick Kind.
The dimension has no known plants, animals, mountains, buildings, or anything. All that is known about it's landform, is that the land is made entirely out of a bunch of grease. It's only known inhabitants are a bunch of elderly old grandmas standing idly around, covered in a bunch of grease, some of them looking very similar to each other. The grandmas seem unaware of any other life forms moving through the world. However, they are aware of interdimensional travelers, as they put together a welcome banner, greeting anyone who comes to their dimension.