Custom Twitch Identity Provider: Bread & Butter

Log in to the developer site of Twitch:

Click Register Your Application.

Enter your App Name. For App Name, we recommend using your organization or company name.
For the OAuth Redirect URL, enter:

https://api.breadbutter.io/callback
For Category, select Website Integration, or any category that describes your integration.
Complete the reCAPTCHA, then click Create.

After your App is created, click Manage.

Copy and save the Client ID and Client Secret for the Bread & Butter setup below.

Go to https://app.breadbutter.io/sign-in/
Click Sign In and authenticate (or Sign Up make a new account and authenticate).
Go to Settings in the left menu.
Click on Twitch under SSO Settings > Social Accounts.
Select "Set Twitch for Production".
Enter a custom name and description.
Enter the Client ID from the Twitch setup steps above.
Enter the Client Secret from the Twitch setup steps above.
Click Save.
Click the checkbox next to your new Twitch provider to enable it.