How do I turn off Microsoft Authenticator?

You have to go to Multi-Factor Authentication in Users menu. Then Click "Service Settings". It doesn't look like a link because Microsoft is stupid and doesn't know how to make it look like a link. Then you'll see the settings you want to disable. Keep in mind, this might take 30 minutes or so for Mircosoft to replicate across all of it's servers. Pictures below

I've disabled it several times - but the next time I login I get forced to "Improve your sign-ins". I really wish Microsoft would quit trying to force their crappy products down my throat. I value my choice. I don't want Edge, Cortana, Bing or their stupid authenticator app.

I can't find any such security tab as Mario mentioned.

Does one of these settings disable the authenticator app?

We're in the same position as most of you. We don't want the authenticator app. MFA is working just fine for us. Being forced to use that will be a real PITA. We have a lot of non-tech savvy users. Changing anything requires a lot of hand-holding. And our users are spread out over 4 counties so not all in the same building either (~325 users).

I've already gone through the process of seting up the authenticator app when the prompt no longer allowed me to click on "Not now" and it was NOT very user friendly. I've turned it off but now I'm back to answering the same prompt as before. I'm wondering how long "Not now" will be available and I have to go through the same process of setting up the authenticator app. ARGH!

"Not now" has disappeared for us now and it's causing havoc. I can't get my job done and people don't want to use it which I don't mind.

I can't even access the Multifactor authentication part of Azure Mike mentioned because I need a "Premium" licence.