Preheat oven to 425° and get out a 13×9 inch casserole.
Cook the beef in a large deep skillet over medium high heat until browned. Drain the beef in a colander and set aside.
Pour ¼ cup of water into the skillet, add onion and carrots and cook over medium heat until softened, about 5 minutes. Stir in tomato paste and then flour and stir for another 2 minutes or so.
Add Worcestershire sauce, 2 cups water, and the cooked beef. Stir in 2 teaspoons of salt and a pinch of pepper and simmer until thickened, stirring occasionally, about 10 minutes. Stir in peas and turn off the heat.
Spoon the beef filling into the casserole and spread the mashed potatoes over the whole thing. Bake until the potato topping is just browned, about 25 to 30 minutes. Serve in warmed bowls. Be very happy.
Notes
Ground Beef: We like the 80/20 fat mixture for this recipe as it’s got the most flavor, ground-beef-wise.
Onion: You can use any variety you like – we find that sweet onions (also called Vidalia onions) are just perfect.
Mashed potatoes: If you have leftover mashies in your fridge, you are good to go. You can also pick up pre-made mashed potatoes in the refrigerated section of your supermarket, and of course you can always make your own mashed potatoes. The only kind we don’t recommend is the dried kind in the box.