I love Italian food.  How about you?
I love Elizabeth David, she was a British Recipe Author, she died in 1992 though, bless her heart
I do not know her.  What did she write
She never wrote anything in particular, she is known mostly for her influence in revitalizing home cookery in her native country in the 20th century.
that is nice.  How did she change cooking?
She was born upper-class and her family had much abided by the customs of a time which she rebelled against and pushed the boundary on traditional cooking.
Did she use more spices or how did she push the boundaries?
She used medieval cuisine inspired elements and spices yes, European cooking is very different from other countries.