Combine the hot water, salt and oil in a large pot over high heat; cover and bring to a boil. When water reaches a rolling boil, add small amounts of spaghetti at a time to the pot, breaking up oil patches as you drop spaghetti in. Return to a boil and cook uncovered at al dente stage (about 4 minutes if fresh, 7 minutes if dry); do not overcook. (During this cooking time, use a wooden or spaghetti spoon to lift spaghetti out of the water by spoonfuls and shake strands back into the boiling water.) Then immediately drain spaghetti off into a colander; stop its cooking by running cold water over strands. (If you used dry spaghetti, first rinse with hot water to wash off starch.) After the spaghetti has cooled thoroughly about 2 to 3 minutes, pour a liberal amount of vegetable oil in your hands and toss spaghetti. Set aside in a colander.
Melt 6 tablespoons of the butter in a large skillet over high heat. Add the seafood, green onions, Magic Seasoning Blend®, and garlic; cook just until seafood is cooked while vigorously shaking the pan in a back-and-forth motion (versus stirring), about 1 minute. Add the stock and the remaining 6 tablespoons of butter. Cook until butter melts, about 1 minute, continuing to shake pan. Add the spaghetti; toss and cook just until spaghetti is heated through, about 1 minute more. Remove from heat and serve immediately.
For each serving, roll spaghetti on a long fork and place on a heated serving plate. Top with remaining sauce.