Scrub and pierce potatoes; rub with oil. Bake at 375° until tender, about 1 hour.
In a large skillet, cook and crumble the beef with onion, peppers and garlic over medium heat until beef is no longer pink; drain. Add the mixed vegetables, Worcestershire sauce, tomato paste, steak seasoning, salt, pepper, cayenne and 1 teaspoon paprika. Cook and stir until vegetables are tender.
When potatoes are cool enough to handle, cut a thin slice off the top of each and discard tops. Scoop out the pulp, leaving thin shells.
In a large bowl, mash the pulp with butter. Add the whipping cream, sour cream, cheeses and chives. Mash potatoes until combined. Spoon 1 cup meat mixture into each potato shell; top with 1/2 cup potato mixture. Sprinkle with remaining 1 teaspoon paprika.
Place on a baking sheet. Bake at 375° for 20 minutes. Sprinkle with cheese; bake until melted, about 5 minutes longer. Sprinkle with chives and paprika.