How to Hide the "BBQ Firewall" Admin Menu

function plt_hide_block_bad_queries_menus() {
	//Hide the "Settings → BBQ Firewall" menu.
	remove_submenu_page('options-general.php', 'bbq_settings');
}

add_action('admin_menu', 'plt_hide_block_bad_queries_menus', 11);

Where do I put this code?