A bag of chips (thick cut potato fries) that contains and arbitrary number of chips more than a regular bag of chips. The amount of extra chips is at the discretion and generally based on the mood of the person serving as there is no standard measure for a large chip.
This is a very, very common thing amongst Irish people when describing a person, place or thing. Because sometimes we can't articulate how large or small an object is, or the skin tone of an individual or even the heat of a local curry dish - we use this a lot! We basically just say the word twice and the person who gets the info knows exactly what we mean by tone alone.
Went quickly or went unencumbered. May have to do without the old idea of having an account or owing money... having a slate, and maybe this the idea of being free from debt...