Meatloaf and Mashed Potato Croquettes

1 lbs potatoes, peeled and cubed 1"
2 tbsp butter
1/4 cup milk
1 egg
1 tsp chives
1/4 tsp salt
1 lbs ground beef
1/4 cup ketchup
3/4 tsp onion salt
1/4 tsp pepper
1/4 cup parmesean cheese
1 tsp paprika

Preheat oven to 375F. In a large saucepan of boiling salted water, cook potatoes until tender. Drain well. Mash potatoes with butter, milk, egg, chives and salt. In a medium bowl, mix beef, ketchup, onion, salt and pepper. Divide meat mixture among 8 muffin cups. With your fingers, press meat mixture evenly against bottoms and sides of each up to form shells. Fill shells with potatoes. Sprinkle cheese and paprika on potatoes. Bake until tops are golden brown and meat shells are cooked through, about 25 minutes.