Combine 1 tablespoon olive oil with Knorr® Beef flavor Bouillon Cube(s) to form a smooth paste. Rub bouillon mixture onto beef. Cut beef into 1 inch strips.
Brown beef in large nonstick skillet over high heat, in batches if necessary, about 2 minutes. Remove beef and set aside.
Heat remaining 2 tablespoons olive oil in same skillte over medium-high heat and cook onion, stirring occasionally, until onion is translucent, about 3 minutes. Stir in mushroom and cook, stirring occasionally, until mushrooms are tender, about 3 minutes. Stir in paprika and cook 2 minutes.
Stir in water and bring to a boil. Stir in Knorr® Pasta Sides™ - Butter flavor and return to a boil. Reduce heat to low and simmer 7 minutes or until pasta is tender. Stir in beef and lemon juice; heat through. Remove from heat and stir in sour cream. Sprinkle with parsley.