Ground Beef and Gravy Over Mashed Potatoes

Ingredients:

For the Mashed Potatoes:

2 pounds potatoes, peeled and quartered
1/2 cup milk
4 tablespoons butter
Salt and pepper to taste
For the Ground Beef and Gravy:
1 pound ground beef
1 medium onion, diced
2 cloves garlic, minced
2 tablespoons all-purpose flour
2 cups beef broth
1 tablespoon Worcestershire sauce