The "Fuck you 'cause we said so" law?

They are free to make it up as they go, as long as nobody stops them.

Case law empowers administrative agencies to interpret statutes, subject to judicial review.
Nearly every statute passed by Congress empowers the administrative agency tasked with enforcing the statute to make rules as past of the enforcement process. That is referred to as delegation of authority.

If you mean the law that allows agencies to adopt rules implementing laws that have already been passed you're probably thinking of what the feds and many states refer to as the "Administrative Procedures Act."

A lot of laws are vague. Law enforcement has the ability to enforce their interpretation unless a court comes up with a different interpretation.

Hence the issue... The legislature creates the law, the executive administers the law.  Administering the law means writing the administrative procedures to be used (regulations).  Unfortunately, the executive seems to be writing rules to enact the law in a manner that does not follow the intent of Congress when they passed the law.  Normally the judicial branch could be used to overturn these rules, but the executive branch has castrated the independent judiciary.  Instead of a representative republic with systematic checks and balances, we now have a monarchy. Having some semblance of control over 1/3 of the government does nothing to reign in the other 2/3's.  Power of the purse?  Give me a veto proof majority and that would be a partial solution to forcing the executive to comply with the intent of the law.  Changing the judiciary takes longer and requires controlling the other two branches.  

Delegated Authority... not a law per say but a mechanism of transfer through Legislative Action with the passage of laws and the creation of angencies.

Most laws include a clause along the lines of: The Department of ______________________ may promulgate such rules and regulations required in order to establish and enforce this law.

Congress doesn't pass real laws anymore.  They pass "frameworks" which allow the agencies to fill in the blanks.  Pelosi wasn't lying when she said "we have to pass the bill so that you can find out what is in it".

seems like the issue is when these 'rules and regulations' take on the force of law and people get fined and jailed for breaking them

The problem we have nowadays is that the courts have abandoned the Nondelegation Doctrine and any semblance of separation of powers between the legislative and executive branch.

The nondelegation doctrine was all but gone in 1984 when the courts decided agencies could interpret the limits of their own authority in Chevron USA v. NRDC, and it was totally eviscerated in 1989 by Mistretta v. US, which held that it's good enough for Congress to enact "broad general directives" leaving agencies with the power to fill in all those annoying little details that have the force of law.

ETA: In my view, abandonment of the nondelegation doctrine is right up there with the bastardization of the commerce clause as the root cause of unbridled expansion of federal authority.

show me a law written by any congress that gives the details on how to implement and administer said law.

they've never provided the detail on how to administer any laws...

They used to. Then the courts let them off the hook when they decided they couldn't be bothered with the details and separation of powers anymore. See the post above yours.