Wash the beef pieces thoroughly and pat dry on paper towels.
Put the meat in a bowl, add in the turmeric powder, 1/2 tsp red chilly powder, 1/2 tsp black pepper powder, 1 tsp vinegar, salt and mix it well.
Marinate this mixture for 30 minutes or so.
After this time period, take a pressure cooker and put in the marinated beef. Let it cook till 3 whistles. Note that there is no need to add water.
After 3 whistles switch off the stove and let the pressure release on its own.
Take a pan/kadai and heat the oil. Once the oil is hot, add in the chopped onions along with the ginger, garlic, green chillies.
Saute and cook till the onions become translucent in colour.
Lower the heat, add in 2 and 1/2 tsp red chilly powder,1/4 tsp cumin powder, 1/2 tsp fennel powder. Fry and cook this mixture for a minute or so.
Then put in the tomatoes and continue cooking till they become soft and separate from the oil.
Finally add in the semi-cooked beef along with the garam masala and 1 and 1/2 tsp black pepper powder.
Let it simmer and cook for 30-45 minutes until the gravy thickens and the meat is wholly cooked. Remember to check and stir in between.
Serve warm with rice or chapatis as desired.