Mierzwa began painting and drawing at an early age as her mother was an illustrator and painter who encouraged her artistic development. After attending the High School of Art & Design, she studied painting and illustration at Parson's School of Design as well as taking courses at the School of Visual Arts, the National Academy of Design and Instituto Allende, located in San Miguel de Allende, Mexico. She also produced specialty designs for clothier J. Crew that appeared on many of its showcase pieces.
She works in a variety of media, with subject matter that includes landscapes of the New York and Connecticut shorelines as well as Cape Cod and Martha's Vineyard.