diff --git a/ChangeLog.md b/ChangeLog.md
--- a/ChangeLog.md
+++ b/ChangeLog.md
@@ -1,5 +1,10 @@
 # ChangeLog for yesod-test
 
+## 1.6.12
+
+* Fix import in cookie example [#1713](https://github.com/yesodweb/yesod/pull/1713)
+* Add `MonadState` instance for `SIO`
+
 ## 1.6.11
 
 * Add missing `HasCallStack`s [#1710](https://github.com/yesodweb/yesod/pull/1710)
diff --git a/Yesod/Test.hs b/Yesod/Test.hs
--- a/Yesod/Test.hs
+++ b/Yesod/Test.hs
@@ -7,6 +7,7 @@
 {-# LANGUAGE ImplicitParams #-}
 {-# LANGUAGE ConstraintKinds #-}
 {-# LANGUAGE GeneralizedNewtypeDeriving #-}
+{-# LANGUAGE MultiParamTypeClasses #-}
 
 {-|
 Yesod.Test is a pragmatic framework for testing web applications built
@@ -245,6 +246,7 @@
 import Control.Monad.Trans.Reader (ReaderT (..))
 import Conduit (MonadThrow)
 import Control.Monad.IO.Class
+import qualified Control.Monad.State.Class as MS
 import System.IO
 import Yesod.Core.Unsafe (runFakeHandler)
 import Yesod.Test.TransversingCSS
@@ -462,7 +464,7 @@
 --
 -- ==== __Examples__
 --
--- > import qualified Data.Cookie as Cookie
+-- > import qualified Web.Cookie as Cookie
 -- > :set -XOverloadedStrings
 -- > testSetCookie Cookie.defaultSetCookie { Cookie.setCookieName = "name" }
 --
@@ -1600,6 +1602,11 @@
 -- @since 1.6.0
 newtype SIO s a = SIO (ReaderT (IORef s) IO a)
   deriving (Functor, Applicative, Monad, MonadIO, MonadThrow, MonadUnliftIO)
+
+instance MS.MonadState s (SIO s)
+  where
+  get = getSIO
+  put = putSIO
 
 getSIO :: SIO s s
 getSIO = SIO $ ReaderT readIORef
diff --git a/yesod-test.cabal b/yesod-test.cabal
--- a/yesod-test.cabal
+++ b/yesod-test.cabal
@@ -1,5 +1,5 @@
 name:               yesod-test
-version:            1.6.11
+version:            1.6.12
 license:            MIT
 license-file:       LICENSE
 author:             Nubis <nubis@woobiz.com.ar>
@@ -34,6 +34,7 @@
                    , pretty-show               >= 1.6
                    , text
                    , time
+                   , mtl                       >= 2.0.0
                    , transformers              >= 0.2.2
                    , wai                       >= 3.0
                    , wai-extra