diff --git a/overlay/sbin/butterknife-provision b/overlay/sbin/butterknife-provision
index 5eb4b73..02a8833 100755
--- a/overlay/sbin/butterknife-provision
+++ b/overlay/sbin/butterknife-provision
@@ -146,9 +146,11 @@ case $BUTTERKNIFE_TRANSFER_METHOD in
         ########################################
         ### Target filesystem creation phase ###
         ########################################
+
         case $BUTTERKNIFE_PARTITIONING_METHOD in
             efi)
-                mkfs.vfat ${BUTTERKNIFE_DISK}1
+                BUTTERKNIFE_EFI_SYSTEM_PARTITION=$(ls ${BUTTERKNIFE_DISK}?* | sort | head -n 1)
+                mkfs.vfat ${BUTTERKNIFE_EFI_SYSTEM_PARTITION}
             ;;
         esac
 
@@ -383,7 +385,7 @@ case $BUTTERKNIFE_PARTITIONING_METHOD in
         
         case $BUTTERKNIFE_PARTITIONING_METHOD in
             efi)
-                mount ${BUTTERKNIFE_DISK}1 $TARGET_MOUNTPOINT/boot/efi
+                mount ${BUTTERKNIFE_EFI_SYSTEM_PARTITION} $TARGET_MOUNTPOINT/boot/efi
             ;;
         esac