Look at the basic, Nominative form of a singular noun.
If it ends with a consonant, it's probably masculine.
If it ends with -a, it's probably feminine.
If it ends with -e, -ę, -o or -um, it's neuter.
There are exceptions to that (e.g. 'mysz' is feminine, 'mężczyzna' or 'tata' are masculine), but the above can be your first thought, and then you learn the exceptions.
As it's written in the comments above, I deleted those options in September. But later we decided to accept them, despite not really being the direct translation... ok, added here.
However, please note that "delicious" definitely is stronger than "tasty", so a better Polish version of your sentence would be "Ser jest pyszny".