Shen Chu Kuang Hou

A top killer from the 21st century accidentally became a loser empress through time travel, and got an extremely handsome husband and a cute genius baby. She gradually figured out that to dominate the imperial harem, she must hone her skills both at cooking and at pleasing the emperor. With her pot and spoon and assisted by a spirit chef system providing her with handy equipment any time, she finally swept the emperor off his feet, took hold of the harem, and reached the pinnacle of her life!

(Source: WebComics)