Sounds like you need the cookbook that I inherited from my grandmother, 365 WAYS TO COOK HAMBURGER, Easy, economical, and excitingly different recipes for 1 to 100 people, by Doyne Nickerson.
Yes, it's a crazy book. (And I'm a vegetarian, so owning it is even sillier.) I like to read it for fun. There are some recipes that seem very bizarre. But, perhaps there is something useful?
Wow, almost all of the recipes require at least an hour of baking, including the meatballs.
So, I say, anything that simply requires frying, would be best. As others have suggested, that means tacos or sloppy joes, or taco salad. You could also create your own recipe, by frying the meat with your favourite seasonings, and then add it to your favourite salad fixings. Or make grilled cheese and ground beef sandwiches?
For next time, when you can cook in advance, I'd suggest trying a meat pie recipe. There are lots of those. Tourtiere is a popular one in Canada.
Cabbage Rolls are another tasty way of using ground beef, but again, they're a bit time consuming. But can be made in advance!