Heat oil in a pan over medium-high heat. Add beef and cook for 3 minutes or so until browned, stirring to crumble. Add the vegetables and cook until soft and fragrant, about 10 minutes.
In the meanwhile, place all the sauce ingredients into a food processor or blender and puree until completely smooth.
Add sauce to the pan. Bring to a boil and then lower the heat and simmer, stirring occasionally for 20-25 minutes, until mixture gets thickened. If too thick, add reserved soaked date water to desired consistency.
note: for the dates, remove the pit and soak in hot water for at least 15 minutes to soften. Reserve the soaked water and add at the end to thin out the sauce, if necessary