In instant pot select Sauté setting; heat oil.

Add onion saute until onion is soft.

Push the onion aside and drop in the ground meat- break it up with a spatula and brown it, about 5 minutes.

Add tomato paste, Worcestershire Sauce salt, pepper and broth; mix well,.

Lower the steamer basket with the sliced potatoes onto the meat.

Close and lock the lid of the pressure cooker; cook for 12 minutes at high pressure.

When time is up, open the pressure cooker with Quick release - pressure through the valve.

Preheat oven to 400 degrees.

Remove the steamer basket from the pressure cooker and toss the frozen peas and corn into the pressure cooker and mix into the meat. leave cooker stand uncovered while you work on the potatoes.

Pour the potatoes into a small mixing bowl. Mash together potatoes with milk, salt and butter.

Pour the contents of the pressure cooker into a deep oven-safe dish.

Spoon and even potatoes over the meat mixture.

Bake un-covered for 20 minutes the potatoes are golden,.

Let casserole stand for 5 minutes before serving.