He said to Jacob, “Let me eat some of that red stew, for I am famished.” (That is why he was also called Edom.)
Jewish Publication Society of America Version (JPS1917) - Genesis 25:30 >And Esau said to Jacob: 'Let me swallow, I pray thee, some of this red, red pottage; for I am faint.' Therefore was his name called Edom.