You can dynamically set the title tag with PHP code using the WordPress pre_get_document_title or document_title_parts filters if you're using Genesis SEO features:
add_filter( 'pre_get_document_title', 'custom_quick_title' );
function custom_quick_title() {
return 'My custom title';
}The document_title_parts filter gives you more fine-grained control if you just wanted to override the title or tagline, for example: