diff --git a/README.rst b/README.rst
index 377f1d2..20da43e 100644
--- a/README.rst
+++ b/README.rst
@@ -528,9 +528,13 @@
         amd64:
           xenial:
             # List of packages, to be installed directly in curtin stage.
-            extra_pkgs: [ "linux-headers-generic-hwe-16.04", "linux-image-extra-virtual-hwe-16.04" ]
+            extra_pkgs:
+              enabled: true
+              pkgs: [ "linux-headers-generic-hwe-16.04", "linux-image-extra-virtual-hwe-16.04" ]
             # exact kernel pkgs name, to be passed into curtin stage.
-            kernel_package: 'linux-image-virtual-hwe-16.04'
+            kernel_package:
+              enabled: true
+              value 'linux-image-virtual-hwe-16.04'
 
 Single MAAS cluster service [multiple racks]
 
diff --git a/maas/files/curtin_userdata_amd64_generic_xenial b/maas/files/curtin_userdata_amd64_generic_xenial
index 0af7280..98c7758 100644
--- a/maas/files/curtin_userdata_amd64_generic_xenial
+++ b/maas/files/curtin_userdata_amd64_generic_xenial
@@ -19,11 +19,6 @@
   maas: [wget, '--no-proxy', {{node_disable_pxe_url|escape.json}}, '--post-data', {{node_disable_pxe_data|escape.json}}, '-O', '/dev/null']
 {% endraw %}
 
-{%- if salt['pillar.get']('maas:cluster:curtin_vars:amd64:xenial:kernel_package') %}
-kernel:
-  package: {{ pillar.maas.cluster.curtin_vars.amd64.xenial.kernel_package }}
-{%- endif %}
-
 {%- if cluster.get('saltstack_repo_key', False) %}
   {% set salt_repo_key = salt['hashutil.base64_b64encode'](cluster.saltstack_repo_key) %}
   apt_00_set_gpg: ["curtin", "in-target", "--", "sh", "-c", "echo '{{salt_repo_key}}' | base64 -d | apt-key add -"]
@@ -36,8 +31,10 @@
 
   apt_01_set_repo: ["curtin", "in-target", "--", "sh", "-c", "echo '{{ saltstack_repo }}' >> /etc/apt/sources.list.d/mcp_saltstack.list"]
   apt_03_update: ["curtin", "in-target", "--", "apt-get", "update"]
-{%- if salt['pillar.get']('maas:cluster:curtin_vars:amd64:xenial:extra_pkgs') %}
-  apt_04_install_pkgs: ["curtin", "in-target", "--", "apt-get", "-y", "install", "{{ pillar.maas.cluster.curtin_vars.amd64.xenial.extra_pkgs|join(' ') }}"]
+{%- if salt['pillar.get']('maas:cluster:curtin_vars:amd64:xenial:extra_pkgs:enabled')|default(false) %}
+  {% for pkg in pillar.maas.cluster.curtin_vars.amd64.xenial.extra_pkgs.pkgs -%}
+  apt_04_install_pkgs_{{ loop.index }}: ["curtin", "in-target", "--", "apt-get", "-y", "install", "{{ pkg }}"]
+  {% endfor %}
 {%- endif %}
   salt_01_install: ["curtin", "in-target", "--", "apt-get", "-y", "install", "salt-minion"]
   salt_02_hostname_set: ["curtin", "in-target", "--", "echo", "{% raw %}{{node.hostname}}{% endraw %}.{{pillar.linux.system.domain}}"]
@@ -51,6 +48,12 @@
   salt_10_recon_max: ["curtin", "in-target", "--", "sh", "-c", "echo 'recon_max: 60000' >> /etc/salt/minion.d/minion.conf"]
   salt_11_recon_randomize: ["curtin", "in-target", "--", "sh", "-c", "echo 'recon_randomize: True' >> /etc/salt/minion.d/minion.conf"]
   salt_12_auth_timeout: ["curtin", "in-target", "--", "sh", "-c", "echo 'auth_timeout: 60' >> /etc/salt/minion.d/minion.conf"]
+
+{%- if salt['pillar.get']('maas:cluster:curtin_vars:amd64:xenial:kernel_package:enabled')|default(false)  %}
+kernel:
+  package: {{ pillar.maas.cluster.curtin_vars.amd64.xenial.kernel_package.value }}
+{%- endif %}
+
 {% raw %}
 {{if third_party_drivers and driver}}
   driver_00_key_get: curtin in-target -- sh -c "/bin/echo -en '{{key_string}}' > /tmp/maas-{{driver['package']}}.gpg"
diff --git a/tests/pillar/maas_region.sls b/tests/pillar/maas_region.sls
index d601e91..d3325eb 100644
--- a/tests/pillar/maas_region.sls
+++ b/tests/pillar/maas_region.sls
@@ -10,9 +10,13 @@
       curtin_vars:
         amd64:
           xenial:
-            extra_pkgs: [ "curl", "wget" ]
-            #kernel_package: 'linux-image-virtual-hwe-16.04'
-            kernel_package: 'mc'
+            extra_pkgs:
+              enabled: true
+              pkgs: [ "curl", "wget" ]
+            kernel_package:
+              enabled: true
+              #value: 'linux-image-virtual-hwe-16.04'
+              value: 'mc'
   region:
     enabled: true
     bind: