Dice the meat and fry in the hot oil in portions, remove. Dice the onions and sauté in the roasting fat. Add the meat again, season. Deglaze with white wine. Braise briefly. Add the stock and bring to a boil. Cover and cook over a low heat for about 1 hour.
Clean, halve and slice the zucchini. Drain the corn. Pluck the thyme leaves. Add the zucchini, corn and thyme to the meat 10 minutes before the end of the cooking time. Whisk the cream and cornstarch together and slightly thicken the goulash while stirring. Season with salt, pepper and lemon juice.