diff --git a/osbuild/util/bls.py b/osbuild/util/bls.py
index c4922bec..a0989593 100644
--- a/osbuild/util/bls.py
+++ b/osbuild/util/bls.py
@@ -3,6 +3,7 @@ Function for appending parameters to
 Boot Loader Specification (BLS).
 """
 import glob
+import os
 from typing import List
 
 
@@ -23,12 +24,16 @@ def options_append(root_path: str, kernel_arguments: List[str]) -> None:
     if len(bls_conf_files) == 0:
         raise RuntimeError(f"no BLS configuration found in {bls_glob}")
     for entry in bls_conf_files:
-        # Read in the file and then append to the options line.
         with open(entry, encoding="utf8") as f:
             lines = f.read().splitlines()
-        with open(entry, "w", encoding="utf8") as f:
+        with open(entry + ".tmp", "w", encoding="utf8") as f:
+            found_opts_line = False
             for line in lines:
-                if line.startswith('options '):
+                if not found_opts_line and line.startswith('options '):
                     f.write(f"{line} {' '.join(kernel_arguments)}\n")
+                    found_opts_line = True
                 else:
                     f.write(f"{line}\n")
+            if not found_opts_line:
+                f.write(f"options {' '.join(kernel_arguments)}\n")
+        os.rename(entry + ".tmp", entry)
diff --git a/test/mod/test_util_bls.py b/test/mod/test_util_bls.py
new file mode 100644
index 00000000..57457b90
--- /dev/null
+++ b/test/mod/test_util_bls.py
@@ -0,0 +1,56 @@
+#
+# Test for the util/bls.py
+#
+
+import textwrap
+
+from osbuild.util import bls
+
+
+def make_fake_bls_file(rootdir, kernel_opts):
+    if kernel_opts:
+        options = f"options {kernel_opts}"
+    else:
+        options = ""
+    bls_path = rootdir / "loader/entries/test.conf"
+    bls_path.parent.mkdir(exist_ok=True, parents=True)
+    bls_path.write_text(textwrap.dedent(f"""\
+    title        Fedora 19 (Rawhide)
+    sort-key     fedora
+    machine-id   6a9857a393724b7a981ebb5b8495b9ea
+    version      3.8.0-2.fc19.x86_64
+    {options}
+    architecture x64
+    linux        /6a9857a393724b7a981ebb5b8495b9ea/3.8.0-2.fc19.x86_64/linux
+    initrd       /6a9857a393724b7a981ebb5b8495b9ea/3.8.0-2.fc19.x86_64/initrd
+    """), encoding="utf8")
+    return bls_path
+
+
+def test_options_append_one(tmp_path):
+    bls_path = make_fake_bls_file(tmp_path, "root=/dev/sda1 quiet")
+    bls.options_append(tmp_path, ["splash", "console=ttyS0"])
+    new_content = bls_path.read_text(encoding="utf8")
+    assert "\noptions root=/dev/sda1 quiet splash console=ttyS0\n" in new_content
+
+
+def test_options_append_none(tmp_path):
+    bls_path = make_fake_bls_file(tmp_path, "")
+    bls.options_append(tmp_path, ["splash", "console=ttyS0"])
+    new_content = bls_path.read_text(encoding="utf8")
+    assert "\noptions splash console=ttyS0\n" in new_content
+
+
+def test_options_append_multiple(tmp_path):
+    bls_path = make_fake_bls_file(tmp_path, "root=/dev/sda1")
+    with bls_path.open("a") as fp:
+        fp.write("options quiet")
+    bls.options_append(tmp_path, ["splash", "console=ttyS0"])
+    new_content = bls_path.read_text(encoding="utf8")
+    options = [line for line in new_content.split("\n")
+               if line.startswith("options ")]
+    # note that the new options only got added once
+    assert options == [
+        "options root=/dev/sda1 splash console=ttyS0",
+        "options quiet",
+    ]