diff --git a/atst/utils/form_cache.py b/atst/utils/form_cache.py
index 583ca611..3ce4f17a 100644
--- a/atst/utils/form_cache.py
+++ b/atst/utils/form_cache.py
@@ -1,5 +1,6 @@
 from hashlib import sha256
 import json
+from werkzeug.datastructures import ImmutableMultiDict
 
 
 DEFAULT_CACHE_NAME = "formcache"
@@ -24,7 +25,8 @@ class FormCache(object):
 
     def read(self, formdata_key, key_prefix=DEFAULT_CACHE_NAME):
         data = self.redis.get(self._key(key_prefix, formdata_key))
-        return json.loads(data) if data is not None else {}
+        dict_data = json.loads(data) if data is not None else {}
+        return ImmutableMultiDict(dict_data)
 
     @staticmethod
     def _key(prefix, hash_):
diff --git a/tests/utils/test_form_cache.py b/tests/utils/test_form_cache.py
index 17998ee7..c399acd1 100644
--- a/tests/utils/test_form_cache.py
+++ b/tests/utils/test_form_cache.py
@@ -1,5 +1,5 @@
 import pytest
-from werkzeug.datastructures import ImmutableDict
+from werkzeug.datastructures import ImmutableMultiDict
 
 from atst.utils.form_cache import DEFAULT_CACHE_NAME, FormCache
 
@@ -10,13 +10,13 @@ def form_cache(app):
 
 
 def test_cache_form_data(app, form_cache):
-    data = ImmutableDict({"kessel_run": "12 parsecs"})
+    data = ImmutableMultiDict({"kessel_run": "12 parsecs"})
     key = form_cache.write(data)
     assert app.redis.get("{}:{}".format(DEFAULT_CACHE_NAME, key))
 
 
 def test_retrieve_form_data(form_cache):
-    data = ImmutableDict({"class": "corellian"})
+    data = ImmutableMultiDict({"class": "corellian"})
     key = form_cache.write(data)
     retrieved = form_cache.read(key)
     assert retrieved == data