In a zip lock bag place in the flour, salt, pepper, paprika and beef strips, seal bag and shake to evenly coat beef in spices.
In a frying pan on high heat 2 tablespoons of oil, place 1/2 of beef strips into pan and fry for 2 minutes or until golden brown, remove from pan. Repeat with other half of beef strips, adding more oil if needed. Remove from pan.
Reduce frying pan to medium pour in remaining oil and saute mushrooms, garlic, onion, carrot and zucchini until softened.
Stir through tomato paste, continue to stir for 1 minute.
Add stock, worcestershire sauce and sour cream to pan, stir.
Place beef back into pan and cook for 1 minute to heat through.
Serve with rice, pasta or mashed potato and a sprinkle of chives.