Melt 2 tablespoons butter in a 12-inch skillet over high heat. When the butter sizzles, add the onions, shake the pan, stir and cook until the onions start to brown, about 4 minutes. Stir in 2 cups corn and 2 teaspoons Vegetable or Seafood Magic and cook until a light crust forms on the bottom of the skillet, about 1 minute. Add 1/2 cup chicken stock and scrape well to remove all the crust from the skillet bottom. Continue to cook without stirring until another hard crust forms on the bottom of the skillet, about 6 to 8 minutes. Add the remaining 2 1/2 cups corn, the lima beans, remaining Vegetable or Seafood Magic and 1 cup chicken stock. Scrape well, stir and cook for 2 minutes. Add the green beans, stir and bring to a simmer, about 2 minutes. Add the remaining 2 tablespoons butter. Stir and cook, flipping and shaking the pan from time to time, for 6 minutes. Stir in the remaining 1 cup chicken stock and cook, stirring occasionally, for 7 minutes. Add the beef stock, stir and cook until the lima beans are tender, about 10 minutes.