Hidden checkout field Woocommerce for current user

Solution:

All you need to do is pass the current users email address into the get_avatar() function.

<?php 

$current_user = wp_get_current_user();

if ( ($current_user instanceof WP_User) ) {
    echo get_avatar( $current_user->user_email, 32 );
}

?>

Here are some links for specifics:

get_avatar(); wp_get_current_user();

To output the profile picture

<?php 

echo '<img src="'. get_the_author_meta( 'user_custom_avatar', $current_user->ID, 32 ) .'" />';

?>