As a Verb or Adjective:
1. To have a very pleasant taste, to taste good. English = (be) delicious. Informal English = (be) yummy.
2. To have an extremely pleasant taste, to taste extremely good. English = (be) scrumptious.
1. Used alone to indicate that you like the food you are eating very much, especially to the person who made it or is responsible for it. English = 'Yummy!'