It is sold in sachets. Well-known brands are Maggi, Radolf and Knorr. Both the Maggi and Knorr sachets weigh 50g (around 2 oz.) One package is enough for a 3 to 4 person serving size batch of goulash, or for a goulash of 500g of unprocessed meat (such as fresh beef, fresh pork, etc) or 250g of sausage. Many recipes call for 2 or 3 sachets.
Many goulash recipes rely on this as the seasoning, but the packages give also directions for making a quick and easy goulash just with the package, meat and water:
From a Maggi sachet:
In a pot, put 1 2/3 cup (13 oz / 400 ml) of water, and mix packet in. Bring to a boil, stirring often. Add meat, bring back to a boil, cover, lower heat to a simmer and simmer until meat is tender, about 1 to 1 1/2 hours, stirring occasionally.
The Knorr ingredients are: Kartoffeln [potatoes], 14% Paprika, Stärke, 9% Zwiebeln [onion], Zucker [sugar], jodiertes Speisesalz [food salt], Tomatenpulver [powdered tomato], Milchzucker [lactose], pflanzliches Fett gehärtet [vegetable fat], Aroma (mit Selleriesaatextrakt) [flavouring with celery extract], Geschmacksverstärker [taste amplifier] (Mononatriumglutamat [MSG], Dinatriumguanylat, Dinatriuminosinat), Weizenmehl [wheat flour], Knoblauch [garlic], Speisesalz [food salt], Farbstoff [food dye] E 150c, Pfeffer [pepper], Majoran [marjoram], Kümmel [caraway], Cayennepfeffer [cayenne pepper], Säuerungsmittel Citronensäure [acidifying material citric acid], Hefeextrakt [yeast extract], Traubenzucker [grape sugar].