At what point were medieval battles fought by professionals instead of the stereotypical peasant levies?

by MundaneInquirer

So, there is a trope that medieval battles were fought by knights supported by barely trained levies. Obviously, at some point this changed, and wars were fought by professional forces.

When was that? Or, if no solid date can be established, when did this transformation take place?

Or were the stereotypical levies never really a thing?

LionoftheNorth

I don't want to discourage further answers but similar questions have been asked in the past. The conclusion, at least with regards to the middle ages, seems to be that peasant levies were relatively rare.

Here are some of the topics on the subject, with answers by /u/Anayalator, /u/MI13, /u/bigbluepanda and /u/Rittermeister among others:

How "professional" were the armies in Western Europe during the High Middles Ages(1066-1453)?

If peasant conscripts made up the bulk of armies historically, why can't they start an uprising?Why can't they beat small armies of elites such as knights?