How to Hide the "[HCB] Settings" Admin Menu

function plt_hide_highlighting_code_block_menus() {
	//Hide the "Settings → [HCB] Settings" menu.
	remove_submenu_page('options-general.php', 'hcb_settings');
}

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

Where do I put this code?