In saucepan, cook potatoes for 15 minutes or until tender.
Drain, mash with milk, butter and half the salt.
Spread in 8 cup casserole dish.
In nonstick skillet cook beef, onion and garlic stirring often for 5 minutes.
Spoon off any fat.
Sprinkle with flour and cook stirring for 2 minutes.
Stir in com, stock, ketchup, Worcestershire, pepper and remaining salt.
Cook for 10 minutes over medium heat.
Spoon over potatoes.
Sprinkle with cheese and broil until melted.
Sprinkle with green pepper.