Heat 2 teaspoons of oil over med-high heat and brown the pork and beef for 4-5 minutes, sprinkling with salt & pepper. Remove to a bowl.In the same pot in 1 teaspoon of oil, brown the onions & garlic for 2-3 minutes until golden brown.Add mushrooms, cook & stir 2 minutes.Add cabbage, cook & stir 2 minutes.Stir tomato paste into chicken stock and add to the pot along with the remaining ingredients. Combine well, burying the meats under the mixture. Cover and simmer 2 hours, stirring occasionally.Remove the pork and beef and shred using 2 forks. Return to pot.