Easy Skillet Shepherd's Pie

extra virgin olive oil

ground beef

medium carrots (chopped in quarters)

medium onion (chopped)

celery stalks (chopped)

garlic cloves (minced)

tomato paste

beef broth/vegetable broth

dried oregano

fresh thyme

salt and freshly ground pepper

leftover mashed potatoes (depending on the size of the dish you are using)