diff --git a/packages/frontend-plugin-api/src/blueprints/SignInPageBlueprint.test.tsx b/packages/frontend-plugin-api/src/blueprints/SignInPageBlueprint.test.tsx
index f97798a64c..61b23e56f9 100644
--- a/packages/frontend-plugin-api/src/blueprints/SignInPageBlueprint.test.tsx
+++ b/packages/frontend-plugin-api/src/blueprints/SignInPageBlueprint.test.tsx
@@ -16,9 +16,11 @@
 
 import React from 'react';
 import { SignInPageBlueprint } from './SignInPageBlueprint';
-import { createExtensionTester } from '@backstage/frontend-test-utils';
+import {
+  createExtensionTester,
+  renderInTestApp,
+} from '@backstage/frontend-test-utils';
 import { screen, waitFor } from '@testing-library/react';
-import { coreExtensionData, createExtension } from '../wiring';
 
 describe('SignInPageBlueprint', () => {
   it('should create an extension with sensible defaults', () => {
@@ -60,20 +62,11 @@ describe('SignInPageBlueprint', () => {
 
     const tester = createExtensionTester(extension);
 
-    expect(tester.data(SignInPageBlueprint.dataRefs.component)).toBeDefined();
+    const Element = tester.data(SignInPageBlueprint.dataRefs.component)!;
 
-    createExtensionTester(
-      createExtension({
-        name: 'dummy',
-        attachTo: { id: 'ignored', input: 'ignored' },
-        output: {
-          element: coreExtensionData.reactElement,
-        },
-        factory: () => ({ element: <div /> }),
-      }),
-    )
-      .add(extension)
-      .render();
+    expect(Element).toBeDefined();
+
+    renderInTestApp(<Element onSignInSuccess={() => {}} />);
 
     await waitFor(() => {
       expect(screen.getByTestId('mock-sign-in')).toBeInTheDocument();
diff --git a/packages/frontend-test-utils/src/app/createExtensionTester.tsx b/packages/frontend-test-utils/src/app/createExtensionTester.tsx
index 4bfc8392cb..2d842062fc 100644
--- a/packages/frontend-test-utils/src/app/createExtensionTester.tsx
+++ b/packages/frontend-test-utils/src/app/createExtensionTester.tsx
@@ -49,57 +49,6 @@ import { instantiateAppNodeTree } from '../../../frontend-app-api/src/tree/insta
 // eslint-disable-next-line @backstage/no-relative-monorepo-imports
 import { readAppExtensionsConfig } from '../../../frontend-app-api/src/tree/readAppExtensionsConfig';
 
-const NavItem = (props: {
-  routeRef: RouteRef<undefined>;
-  title: string;
-  icon: IconComponent;
-}) => {
-  const { routeRef, title, icon: Icon } = props;
-  const link = useRouteRef(routeRef);
-  if (!link) {
-    return null;
-  }
-  return (
-    <li>
-      <Link to={link()}>
-        <Icon /> {title}
-      </Link>
-    </li>
-  );
-};
-
-const TestAppNavExtension = createExtension({
-  namespace: 'app',
-  name: 'nav',
-  attachTo: { id: 'app/layout', input: 'nav' },
-  inputs: {
-    items: createExtensionInput({
-      target: createNavItemExtension.targetDataRef,
-    }),
-  },
-  output: {
-    element: coreExtensionData.reactElement,
-  },
-  factory({ inputs }) {
-    return {
-      element: (
-        <nav>
-          <ul>
-            {inputs.items.map((item, index) => (
-              <NavItem
-                key={index}
-                icon={item.output.target.icon}
-                title={item.output.target.title}
-                routeRef={item.output.target.routeRef}
-              />
-            ))}
-          </ul>
-        </nav>
-      ),
-    };
-  },
-});
-
 /** @public */
 export class ExtensionQuery {
   #node: AppNode;
@@ -245,6 +194,25 @@ export class ExtensionTester {
     return new ExtensionQuery(node);
   }
 
+  element(): JSX.Element {
+    const tree = this.#resolveTree();
+
+    const element = new ExtensionQuery(tree.root).data(
+      coreExtensionData.reactElement,
+    );
+
+    if (!element) {
+      throw new Error(
+        'No element found. Make sure the extension has a `coreExtensionData.reactElement` output, or use the `.get(myComponentDataRef)` method to get the component',
+      );
+    }
+
+    return element;
+  }
+
+  /**
+   * @deprecated Switch to using `renderInTestApp` directly and using `.element()` or `.get(myComponentDataRef)` to get the component you would like to wrap up
+   */
   render(options?: { config?: JsonObject }): RenderResult {
     const { config = {} } = options ?? {};
 
@@ -260,7 +228,6 @@ export class ExtensionTester {
         createExtensionOverrides({
           extensions: [
             ...this.#extensions.map(extension => extension.definition),
-            TestAppNavExtension,
             createRouterExtension({
               namespace: 'test',
               Component: ({ children }) => (
diff --git a/packages/frontend-test-utils/src/app/renderInTestApp.tsx b/packages/frontend-test-utils/src/app/renderInTestApp.tsx
index e0483f68d8..d828c89f12 100644
--- a/packages/frontend-test-utils/src/app/renderInTestApp.tsx
+++ b/packages/frontend-test-utils/src/app/renderInTestApp.tsx
@@ -16,11 +16,24 @@
 
 import React from 'react';
 import {
+  ExtensionDefinition,
+  IconComponent,
   RouteRef,
   coreExtensionData,
   createExtension,
+  createExtensionInput,
+  createExtensionOverrides,
+  createNavItemExtension,
+  createRouterExtension,
+  useRouteRef,
 } from '@backstage/frontend-plugin-api';
-import { createExtensionTester } from './createExtensionTester';
+import { Link, MemoryRouter } from 'react-router-dom';
+import { createSpecializedApp } from '@backstage/frontend-app-api';
+import { render } from '@testing-library/react';
+import { resolveExtensionDefinition } from '@backstage/frontend-plugin-api/src/wiring/resolveExtensionDefinition';
+import { resolve } from 'path';
+import { ConfigReader } from '@backstage/config';
+import { JsonObject } from '@backstage/types';
 
 /**
  * Options to customize the behavior of the test app.
@@ -44,8 +57,64 @@ export type TestAppOptions = {
    * ```
    */
   mountedRoutes?: { [path: string]: RouteRef };
+
+  /**
+   * Additional configuration passed to the app when rendering elements inside it.
+   */
+  config?: JsonObject;
 };
 
+const NavItem = (props: {
+  routeRef: RouteRef<undefined>;
+  title: string;
+  icon: IconComponent;
+}) => {
+  const { routeRef, title, icon: Icon } = props;
+  const link = useRouteRef(routeRef);
+  if (!link) {
+    return null;
+  }
+  return (
+    <li>
+      <Link to={link()}>
+        <Icon /> {title}
+      </Link>
+    </li>
+  );
+};
+
+const TestAppNavExtension = createExtension({
+  namespace: 'app',
+  name: 'nav',
+  attachTo: { id: 'app/layout', input: 'nav' },
+  inputs: {
+    items: createExtensionInput({
+      target: createNavItemExtension.targetDataRef,
+    }),
+  },
+  output: {
+    element: coreExtensionData.reactElement,
+  },
+  factory({ inputs }) {
+    return {
+      element: (
+        <nav>
+          <ul>
+            {inputs.items.map((item, index) => (
+              <NavItem
+                key={index}
+                icon={item.output.target.icon}
+                title={item.output.target.title}
+                routeRef={item.output.target.routeRef}
+              />
+            ))}
+          </ul>
+        </nav>
+      ),
+    };
+  },
+});
+
 /**
  * @public
  * Renders the given element in a test app, for use in unit tests.
@@ -54,20 +123,28 @@ export function renderInTestApp(
   element: JSX.Element,
   options?: TestAppOptions,
 ) {
-  const extension = createExtension({
-    namespace: 'test',
-    attachTo: { id: 'app', input: 'root' },
-    output: {
-      element: coreExtensionData.reactElement,
-    },
-    factory: () => ({ element }),
-  });
-  const tester = createExtensionTester(extension);
+  const extensions: Array<ExtensionDefinition<any, any>> = [
+    createExtension({
+      namespace: 'test',
+      attachTo: { id: 'app/routes', input: 'routes' },
+      output: [coreExtensionData.reactElement, coreExtensionData.routePath],
+      factory: () => {
+        return [
+          coreExtensionData.reactElement(element),
+          coreExtensionData.routePath('/'),
+        ];
+      },
+    }),
+    createRouterExtension({
+      namespace: 'test',
+      Component: ({ children }) => <MemoryRouter>{children}</MemoryRouter>,
+    }),
+  ];
 
   if (options?.mountedRoutes) {
     for (const [path, routeRef] of Object.entries(options.mountedRoutes)) {
       // TODO(Rugvip): add support for external route refs
-      tester.add(
+      extensions.push(
         createExtension({
           kind: 'test-route',
           name: path,
@@ -84,5 +161,17 @@ export function renderInTestApp(
       );
     }
   }
-  return tester.render();
+
+  const app = createSpecializedApp({
+    features: [
+      createExtensionOverrides({
+        extensions,
+      }),
+    ],
+    config: ConfigReader.fromConfigs([
+      { context: 'render-config', data: options?.config ?? {} },
+    ]),
+  });
+
+  return render(app.createRoot());
 }