Genesis includes a widget in the genesis > lib > widgets > user-profile-widget.php.
The code includes a filter you can use in your child themes functions file to add, remove or modify Gravatar image sizes.
$sizes = apply_filters( 'genesis_gravatar_sizes', $sizes );
Firstly, here’s what the widget looks like in the Widgets admin page after adding 2 additional image sizes:
Based on the following question, i’ll give you the code you can use to add additional custom image sizes.
I would like to add some larger image size options to the Genesis – User Profile widget, anyone know how to do this?
Here’s the PHP code you can copy from the view raw link in the Gist and paste at the end of your child themes functions file using a code editor.