An informal word for 'tasty', used more by children, girls and women, is 'yummy'. It comes from the exclamation 'yum', the response that you make when you eat something tasty. The opposite is the equally childish word 'yucky'. You can use either of those in informal situations.
Then there's the standard word 'delicious'. Note that it's an ungradeable adjective, so we wouldn't normally say 'very delicious'.
You could also use other more general adjectives, such as 'gorgeous', which can apply to any sense (taste, touch, smell, sight, sound).