diff --git a/core/modules/layout_builder/src/Plugin/Block/TestContentBlock.php b/core/modules/layout_builder/src/Plugin/Block/TestContentBlock.php
new file mode 100644
index 0000000000..2d8c431f26
--- /dev/null
+++ b/core/modules/layout_builder/src/Plugin/Block/TestContentBlock.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace Drupal\layout_builder\Plugin\Block;
+
+use Drupal\Core\Block\BlockBase;
+
+/**
+ * Provides a 'Test content' block.
+ *
+ * @Block(
+ *   id = "test_content",
+ *   admin_label = @Translation("Test Content")
+ * )
+ */
+class TestContentBlock extends BlockBase {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function defaultConfiguration() {
+    return [
+      'label_display' => FALSE,
+      'text' => '',
+    ];
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function build() {
+    return ['#markup' => $this->configuration['text']];
+  }
+
+}
diff --git a/core/modules/layout_builder/tests/src/Kernel/LayoutSectionFormatterTest.php b/core/modules/layout_builder/tests/src/Kernel/LayoutSectionFormatterTest.php
index fe540d0f45..c391ed92d4 100644
--- a/core/modules/layout_builder/tests/src/Kernel/LayoutSectionFormatterTest.php
+++ b/core/modules/layout_builder/tests/src/Kernel/LayoutSectionFormatterTest.php
@@ -80,21 +80,31 @@ protected function setUp() {
    *
    * @dataProvider providerTestLayoutSectionFormatter
    */
-  public function testLayoutSectionFormatter($layout, $section, $expected_selector, $expected_content) {
-    $entity = EntityTest::create([]);
-    $entity->{$this->fieldName}->layout = $layout;
-    $entity->{$this->fieldName}->section = $section;
+  public function testLayoutSectionFormatter($layout_data, $expected_selector, $expected_content) {
+    $values = [];
+    $values[$this->fieldName] = $layout_data;
+    $entity = EntityTest::create($values);
 
     // Build and render the content.
     $content = $this->display->build($entity);
     $this->render($content);
 
     // Find the given selector.
-    $element = $this->cssSelect($expected_selector);
-    $this->assertNotEmpty($element);
+    if (!is_array($expected_selector)) {
+      $expected_selector = [$expected_selector];
+    }
+    foreach ($expected_selector as $selector) {
+      $element = $this->cssSelect($selector);
+      $this->assertNotEmpty($element);
+    }
 
     // Find the given content.
-    $this->assertRaw($expected_content);
+    if (!is_array($expected_content)) {
+      $expected_content = [$expected_content];
+    }
+    foreach ($expected_content as $content) {
+      $this->assertRaw($content);
+    }
   }
 
   /**
@@ -103,17 +113,61 @@ public function testLayoutSectionFormatter($layout, $section, $expected_selector
   public function providerTestLayoutSectionFormatter() {
     $data = [];
     $data[] = [
-      'layout_onecol',
       [
-        'content' => [
-          'this_should_be_a_UUID' => [
-            'plugin_id' => 'system_powered_by_block',
-          ],
+        [
+          'layout' => 'layout_onecol',
+          'section' => [
+            'content' => [
+              'baz' => [
+                'plugin_id' => 'system_powered_by_block'
+              ]
+            ]
+          ]
         ],
       ],
       '.layout--onecol',
       'Powered by',
     ];
+    $data[] = [
+      [
+        [
+          'layout' => 'layout_onecol',
+          'section' => [
+            'content' => [
+              'baz' => [
+                'plugin_id' => 'system_powered_by_block'
+              ]
+            ]
+          ]
+        ],
+        [
+          'layout' => 'layout_twocol',
+          'section' => [
+            'left' => [
+              'foo' => [
+                'plugin_id' => 'test_content',
+                'text' => 'foo text'
+              ]
+            ],
+            'right' => [
+              'bar' => [
+                'plugin_id' => 'test_content',
+                'text' => 'bar text'
+              ]
+            ]
+          ]
+        ]
+      ],
+      [
+        '.layout--onecol',
+        '.layout--twocol'
+      ],
+      [
+        'Powered by',
+        'foo text',
+        'bar text'
+      ],
+    ];
     return $data;
   }