Milk Maids

Cardamine californica (Milkmaids) (also Dentaria californica), is a flowering plant in the family Brassicaceae, native to western North America from Washington to California and Baja California. It is common in a variety of habitats including shady slopes, open woodlands, chapparal and grasslands in the winter and early spring. In the San Francisco Bay Area it is one of the first wildflowers to bloom, with blossoms from January to May.
Wikipedia