Preheat oven to 180°C .
Cut the beef steaks into thin strips . Heat the oil in a oven proof baking or casserole dish , on the stove , then add the beef strips , garlic , oregano , salt and the cracked black pepper and cook for about 1 minute , tossing them around to seal the meat .
Peel the potatoes and carrots . Cut the potatoes into about 6th and cut the carrot into thirds and the thirds in half again . Then add both the prepared potatoes and carrots into the casserole dish with the prepared steak pieces and mix a little .
Now add the worcestershire sauce and enough beef stock to cover all the ingredients and stir . Now cover the casserole dish and place in the Preheated oven and cook 35/40 minutes or until potatoes and carrots start to become tender , now add the cherry tomato quarters and the baby spinach leaves , stir to combine and place back into the hot oven uncovered for a further 10/15 minutes or until all is tender and cooked .
Remove from the oven and now add the sour cream and stir well to combine thoroughly .
Serve hot with bread to mop up the juices , enjoy . :-) .