Melt The Butter In A Large Skillet Over Medium Heat. Stir In The Onion, Mushrooms, And Brown Sugar. Cook And Stir Until The Onion Has Cooked To A Deep Brown Color, About 10 Minutes. Remove The Caramelized Onions And Set Aside. Fill A Large Pot With Lightly Salted Water And Bring To A Rolling Boil Over High Heat. Once The Water Is Boiling, Stir In The Gnocchi And Return To A Boil. Cook Until The Gnocchi Floats To The Top, About 3 Minutes; Drain, And Keep Warm. Place The Skillet Over Medium-High Heat, And Stir In The Shrimp. Cook And Stir Until The Shrimp Have Turned Pink On The Outside And Are No Longer Translucent In The Center, About 5 Minutes. Add The Caramelized Onions, Sour Cream, Paprika, And Saffron. Cook And Stir Until The Mixture Begins To Simmer, Then Gently Fold In The Cooked Gnocchi, Then Season To Taste With Salt. Pour The Gnocchi Into A Serving Dish, And Sprinkle With Shredded Basil And Parmesan Cheese To Serve.