Bring 6 quarts of water to boil in a large spaghetti pot and add 2 tablespoons of salt.
Remove stem ends from tomatoes and chop tomatoes into 1/4-inch cubes, reserving all juices. In a 12-inch to 14-inch saute pan, heat olive oil until, smoking. Add garlic and cook 30 seconds until light brown. Add tomatoes and juices and cook 2 minutes. Add olives and remove from heat. Cut smoked Mozzarella into 1/4-inch cubes and set aside. Drop gnocchi into boiling water and cook until they float (about 3 minutes). Drain gnocchi into colander and carefully pour them in to pan with tomato mixture. Return to heat and toss gently until bubbling. Add Mozzarella, marjoram leaves and season with salt and pepper. Pour into heated serving dish and serve immediately.