diff --git a/src/Twilio.AspNet.Core/MinimalApiTwiMLResult.cs b/src/Twilio.AspNet.Core/MinimalApiTwiMLResult.cs
index 6b5e9f7..a519615 100644
--- a/src/Twilio.AspNet.Core/MinimalApiTwiMLResult.cs
+++ b/src/Twilio.AspNet.Core/MinimalApiTwiMLResult.cs
@@ -41,5 +41,6 @@ public partial class TwiMLResult : IResult
     /// Writes the TwiML to the HTTP response body
     /// </summary>
     /// <param name="httpContext">The HttpContext containing the Response to write the TwiML to</param>
-    public Task ExecuteAsync(HttpContext httpContext) => WriteTwiMLToResponse(httpContext.Response);
+    public Task ExecuteAsync(HttpContext httpContext) 
+        => WriteTwiMLToResponse(httpContext.Response, httpContext.RequestAborted);
 }
\ No newline at end of file
diff --git a/src/Twilio.AspNet.Core/TwiMLResult.cs b/src/Twilio.AspNet.Core/TwiMLResult.cs
index 9f6f648..9973d9b 100644
--- a/src/Twilio.AspNet.Core/TwiMLResult.cs
+++ b/src/Twilio.AspNet.Core/TwiMLResult.cs
@@ -1,4 +1,5 @@
-using System.Threading.Tasks;
+using System.Threading;
+using System.Threading.Tasks;
 using System.Xml.Linq;
 using Microsoft.AspNetCore.Http;
 using Microsoft.AspNetCore.Mvc;
@@ -17,7 +18,7 @@ public partial class TwiMLResult : IActionResult
         public TwiMLResult(TwiML.TwiML twiml) : this(twiml, SaveOptions.None)
         {
         }
-        
+
         /// <param name="twiml">The TwiML to respond with</param>
         /// <param name="formattingOptions">Specifies how to format TwiML</param>
         public TwiMLResult(TwiML.TwiML twiml, SaveOptions formattingOptions)
@@ -29,20 +30,29 @@ public TwiMLResult(TwiML.TwiML twiml, SaveOptions formattingOptions)
         public async Task ExecuteResultAsync(ActionContext actionContext)
         {
             var response = actionContext.HttpContext.Response;
-            await WriteTwiMLToResponse(response);
+            await WriteTwiMLToResponse(response, actionContext.HttpContext.RequestAborted)
+                .ConfigureAwait(false);
         }
-        
-        private async Task WriteTwiMLToResponse(HttpResponse response)
+
+        private async Task WriteTwiMLToResponse(HttpResponse response, CancellationToken cancellationToken)
         {
             response.ContentType = "application/xml";
             if (twiml == null)
             {
-                await response.WriteAsync("<Response></Response>");
+                await response.WriteAsync("<Response></Response>", cancellationToken)
+                    .ConfigureAwait(false);
                 return;
             }
 
-            var data = twiml.ToString(formattingOptions);
-            await response.WriteAsync(data);
+            var doc = twiml.ToXDocument();
+
+#if NET5_0_OR_GREATER
+            await doc.SaveAsync(response.Body, formattingOptions, cancellationToken)
+                .ConfigureAwait(false);
+#else
+            await response.WriteAsync(doc.ToString(formattingOptions), cancellationToken)
+                .ConfigureAwait(false);
+#endif
         }
     }
-}
+}
\ No newline at end of file
diff --git a/src/Twilio.AspNet.Core/ValidateRequestAttribute.cs b/src/Twilio.AspNet.Core/ValidateRequestAttribute.cs
index a4189ce..2c05627 100644
--- a/src/Twilio.AspNet.Core/ValidateRequestAttribute.cs
+++ b/src/Twilio.AspNet.Core/ValidateRequestAttribute.cs
@@ -60,7 +60,7 @@ public override void OnActionExecuting(ActionExecutingContext filterContext)
                 var httpContext = filterContext.HttpContext;
                 var request = httpContext.Request;
                 string urlOverride = null;
-                if (BaseUrlOverride != null)
+                if (!string.IsNullOrEmpty(BaseUrlOverride))
                 {
                     urlOverride = $"{BaseUrlOverride}{request.Path}{request.QueryString}";
                 }
diff --git a/src/Twilio.AspNet.Core/ValidateTwilioRequestFilter.cs b/src/Twilio.AspNet.Core/ValidateTwilioRequestFilter.cs
index fb01f8b..f72b233 100644
--- a/src/Twilio.AspNet.Core/ValidateTwilioRequestFilter.cs
+++ b/src/Twilio.AspNet.Core/ValidateTwilioRequestFilter.cs
@@ -28,7 +28,7 @@ public ValidateTwilioRequestFilter(IServiceProvider serviceProvider)
         AllowLocal = options.AllowLocal ?? true;
     }
 
-    public async ValueTask<object> InvokeAsync(
+    public ValueTask<object> InvokeAsync(
         EndpointFilterInvocationContext efiContext,
         EndpointFilterDelegate next
     )
@@ -36,17 +36,17 @@ EndpointFilterDelegate next
         var httpContext = efiContext.HttpContext;
         var request = httpContext.Request;
         string urlOverride = null;
-        if (BaseUrlOverride != null)
+        if (!string.IsNullOrEmpty(BaseUrlOverride))
         {
             urlOverride = $"{BaseUrlOverride}{request.Path}{request.QueryString}";
         }
 
         if (RequestValidationHelper.IsValidRequest(httpContext, AuthToken, urlOverride, AllowLocal))
         {
-            return await next(efiContext);
+            return next(efiContext);
         }
 
-        return Results.StatusCode((int) HttpStatusCode.Forbidden);
+        return ValueTask.FromResult((object)Results.StatusCode((int) HttpStatusCode.Forbidden));
     }
 }
 
diff --git a/src/Twilio.AspNet.Core/ValidateTwilioRequestMiddleware.cs b/src/Twilio.AspNet.Core/ValidateTwilioRequestMiddleware.cs
index fce0aee..99040a5 100644
--- a/src/Twilio.AspNet.Core/ValidateTwilioRequestMiddleware.cs
+++ b/src/Twilio.AspNet.Core/ValidateTwilioRequestMiddleware.cs
@@ -24,12 +24,12 @@ IOptions<TwilioRequestValidationOptions> options
             this.options = options.Value ?? throw new Exception("RequestValidationOptions is not configured.");
         }
 
-        public async Task InvokeAsync(HttpContext context)
+        public Task InvokeAsync(HttpContext context)
         {
             var request = context.Request;
 
             string urlOverride = null;
-            if (options.BaseUrlOverride != null)
+            if (!string.IsNullOrEmpty(options.BaseUrlOverride))
             {
                 urlOverride = $"{options.BaseUrlOverride.TrimEnd('/')}{request.Path}{request.QueryString}";
             }
@@ -38,10 +38,10 @@ public async Task InvokeAsync(HttpContext context)
             if (!isValid)
             {
                 context.Response.StatusCode = (int) HttpStatusCode.Forbidden;
-                return;
+                return Task.CompletedTask;
             }
 
-            await next(context);
+            return next(context);
         }
     }
 
diff --git a/src/Twilio.AspNet.Mvc/TwiMLResult.cs b/src/Twilio.AspNet.Mvc/TwiMLResult.cs
index 76296bd..c4fdaf1 100644
--- a/src/Twilio.AspNet.Mvc/TwiMLResult.cs
+++ b/src/Twilio.AspNet.Mvc/TwiMLResult.cs
@@ -30,13 +30,8 @@ public override void ExecuteResult(ControllerContext controllerContext)
                 return;
             }
 
-            var twimlString = dataTwiml.ToString(formattingOptions);
-            if (encoding != "utf-8")
-            {
-                twimlString = twimlString.Replace("utf-8", encoding);
-            }
-
-            response.Output.Write(twimlString);
+            var doc = dataTwiml.ToXDocument();
+            doc.Save(response.Output, formattingOptions);
         }
     }
 }
\ No newline at end of file
diff --git a/src/Twilio.AspNet.Mvc/ValidateRequestAttribute.cs b/src/Twilio.AspNet.Mvc/ValidateRequestAttribute.cs
index df185a7..e2f98af 100644
--- a/src/Twilio.AspNet.Mvc/ValidateRequestAttribute.cs
+++ b/src/Twilio.AspNet.Mvc/ValidateRequestAttribute.cs
@@ -56,7 +56,7 @@ public override void OnActionExecuting(ActionExecutingContext filterContext)
         {
             var httpContext = filterContext.HttpContext;
             string urlOverride = null;
-            if (BaseUrlOverride != null)
+            if (!string.IsNullOrEmpty(BaseUrlOverride))
             {
                 urlOverride = $"{BaseUrlOverride}{httpContext.Request.Path}{httpContext.Request.QueryString}";
             }
diff --git a/src/testapps/AspNetCore/Program.cs b/src/testapps/AspNetCore/Program.cs
index 030eb40..5a36f8f 100644
--- a/src/testapps/AspNetCore/Program.cs
+++ b/src/testapps/AspNetCore/Program.cs
@@ -30,7 +30,6 @@
     app.UseSwaggerUI();
 }
 
-app.UseHttpsRedirection();
 app.UseStaticFiles();
 
 app.UseRouting();