Brown the ground beef in a medium skillet, breaking it up with a large spoon as it cooks.
When just slightly pink, add the carrots, onion, garlic, and a pinch of salt and pepper.
Continue cooking for about 3 more minutes, then stir in the frozen green beans. Cook for another 3 minutes, then add the sliced mushrooms.
Season with salt, pepper, oregano, and ground cumin.
Allow the mushrooms to heat through, for another minute or two. Check the green beans and carrots with a fork to make sure they are crisp-tender.
If the dish is too dry, add in 1/4 cup of beef broth or water and cook for an additional 2 minutes.
Taste for seasoning and adjust as needed.