Non Non Biyori It's almost as slice of life as it gets and is full of cute girls. When I need something to clear my mind from negativity this is my go-to anime. Because of how down to earth it is it's not for everyone because there's nothing much exciting happening the majority of the time, but I can't get enough watching these girls having a great life.
Almost at the same spot would be Yuru Yuri where my darling Akari is from, which is my go-to anime If I need a laugh.