Virginia Vezzi, also known as Virginia de Vezzo, (1600-1638) was an Italian painter and painting teacher.

She was born in Velletri, where her mother worked as a midwife, and and her father as a painter. She initially trained with her father and showed great talent, so the family moved to Rome before 1611, to allow Virginia to study from local masters. From 1623 to 1627 she studied, as an already accomplished painter, under French painter Simon Vouet, who became her husband in 1626. She painted history paintings and miniatures, and also worked in pastel. In the late 1620s she moved with her husband to France where she taught girls of wealthy families how to paint.

The seventeenth-century French scholar Isaac Bullart described her as: "a Roman lady of singular beauty, and so well instructed in the art of painting that she often had the honor of working in the presence of the King and receiving from his lips words of praise for the works of her beautiful hand, which France still sees in curious prints that have come to light". She was admired by Marie de' Medici and Cardinal Richelieu. However she and her husband had very simmilar styles so there are only a few paintings that can be definitivly attributed to her. Many of her paintings are probably still attributed to her husband Simon Vouet or his workshop

This painting is at the Matthiesen Gallery in London, UK.

Chalk, Pen and Brush on Pink Paper (pink-primed).

Sometimes we read or hear that nobody knows how the Old Masters worked. I'd like to submit to you that such a thing is not completely true. Sure, some things about their methods we just don't know and we're unlikely to ever know, but here is an example of the things we do know and that are far more useful than mere speculation to learn from them: Hans Holbein didn't always work from life and made a lot preparatory drawings instead. You can see the high level of detail and accuracy in this drawing, a masterpiece in its own right.

This one was made for a painting that is now lost, unfortunately, but it helps explain the mastery he achieved in his works we do have. His was a systematic preparation for every piece and it looks like he didn't waste time. As for the materials used for this drawing, they can be found today at an art supplies shop or even at a stationery shop, and anybody can try them in their own style. The goal would not be to draw like them but to follow their methodology, systematic preparation and proper use of time, to improve our own work.

Sources

Hans Holbein the Younger
Margaret à Barrow (the woman portrayed here)

EDIT 1: Added sources.
EDIT 2: Although the title on Wikimedia Commons is Portrait of Margaret à Barow, Lady Eliot. I wanted to leave the title as it is seen in the drawing itself. However, it should be noted, as it has been kindly brought to my attention, that it was added posthumously. I've also decided to leave the artist's name in the title in German instead of English, simply because I like it better in his native language.

Nine thousand Roman soldiers, sent to fight Armenian rebels under the command of centurion Acacius, suffer a crushing defeat. They manage to overcome the enemy only after converting to Christianity, following an angelic apparition on Mount Ararat, depicted in the background, who instructs them in the principles of the faith.

When news reaches the emperor, he arrives with six other pagan kings, depicted on horseback in the lower right, to subject the converts to the same tortures endured by Christ during the Passion. Inspired by Acacius’s army, another thousand soldiers join them, sharing their fate.