1 files changed, 2 insertions, 1 deletions
diff --git a/src/csharp/Grpc.IntegrationTesting/TestCredentials.cs b/src/csharp/Grpc.IntegrationTesting/TestCredentials.cs
index 10df704f1d..401c50b1ae 100644
--- a/src/csharp/Grpc.IntegrationTesting/TestCredentials.cs
+++ b/src/csharp/Grpc.IntegrationTesting/TestCredentials.cs
@@ -33,6 +33,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Collections.Immutable;
 using System.Diagnostics;
 using System.IO;
 using System.Text.RegularExpressions;
@@ -77,7 +78,7 @@ namespace Grpc.IntegrationTesting
             var keyCertPair = new KeyCertificatePair(
                 File.ReadAllText(ServerCertChainPath),
                 File.ReadAllText(ServerPrivateKeyPath));
-            return new SslServerCredentials(new List<KeyCertificatePair> { keyCertPair });
+            return new SslServerCredentials(ImmutableList.Create(keyCertPair));
         }
     }
 }