Mom's meatloaf

Our favorite meatloaf recipe. I got this recipe over 20 years ago from a colleague who grew up as the youngest of ten kids on a farm in North Dakota-her family's recipe.

1.5-2 lbs hamburger (I usually blend 1 lb hamburger and 1 lb ground pork)
1 c dry uncooked oatmeal
2 eggs, beaten
1 c milk
1 small onion, chopped (about 1/2 c)
1-2 tsp salt
1/4 tsp pepper
1 tbsp prepared mustard

Mix these and put mixture into a mound in a big casserole.
Topping:
2-3 Tbsp brown sugar
1/4 tsp nutmeg
1/4 c ketchup
1 tsp dry mustard powder

mix topping and spread over raw meatloaf

Bake at 350 for 45-60 min. Internal temp has to be at least 160F.