Preheat oven to 325°F (163°C).

In a large mixing bowl, combine ground beef, rolled oats, beaten egg, dried onion flakes, kosher salt, black pepper, and sweetened condensed milk.

Mix all ingredients thoroughly.

Pat the mixture into a 9-inch round pie plate, ensuring it's evenly distributed and flat.

In a separate small bowl, prepare the savory sauce by mixing ketchup, brown sugar, and dry mustard.

Spoon the savory sauce evenly over the meatloaf.

Place the pie plate with the meatloaf in the preheated oven.

Bake for 1 hour and 15 minutes, or until the sauce is bubbling and the meatloaf is cooked through.

Let the meatloaf rest for a few minutes before slicing and serving.

Enjoy!