diff --git a/stack.sh b/stack.sh
index 0f009fc..c9ca43f 100755
--- a/stack.sh
+++ b/stack.sh
@@ -1266,7 +1266,7 @@
     sudo dnsmasq --conf-file= --port=0 --enable-tftp --tftp-root=/tftpboot \
         --dhcp-boot=pxelinux.0 --bind-interfaces --pid-file=/var/run/dnsmasq.pid \
         --interface=$BM_DNSMASQ_IFACE --dhcp-range=$BM_DNSMASQ_RANGE \
-        ${$BM_DNSMASQ_DNS:+--dhcp-option=option:dns-server,$BM_DNSMASQ_DNS}
+        ${BM_DNSMASQ_DNS:+--dhcp-option=option:dns-server,$BM_DNSMASQ_DNS}
     # ensure callback daemon is running
     sudo pkill nova-baremetal-deploy-helper || true
     screen_it baremetal "nova-baremetal-deploy-helper"