Itemscontrol Modify control template

Question

I want to modify itemscontrol template to modify not how each item apears but the actual itemscontrol

 <ItemsControl
         ItemsSource="{Binding RB}" Grid.Row="1"
         ItemTemplate="{StaticResource myBTemplate}">
         <ItemsControl.ItemsPanel>
                  <ItemsPanelTemplate>
                           <StackPanel></StackPanel>
                  </ItemsPanelTemplate>
         </ItemsControl.ItemsPanel>
 </ItemsControl>

I have this and it's works fine, I get a stackpanel behaviour of items and my custom data template for each item but I can't find a way to modify the container. Let's say to put the title into my items list without doing so outside itemscontrol. and if i do set ControlTemplate items no longer get displayed. (This Itemscontrol is part of an upper level DataTemplate)

Answer 1

After Clemens comment i searched more on Items presenter rather that ControlTemplate.

Found i just needed to add items presenter somewhere in the ControlTemplate with no special tag just respecting tree format.

<ItemsControl
  ItemsSource="{Binding RB}" Grid.Row="1"
  ItemTemplate="{StaticResource myBTemplate}">
         <ItemsControl.Template>
           <ControlTemplate TargetType="{x:Type ItemsControl}">
             <StackPanel>
              <Grid Margin="5" Height="50">
               <Ellipse Stroke="DarkBlue" StrokeThickness="2">
                  <Ellipse.Fill>
                    <RadialGradientBrush Center="0.3,0.2" RadiusX="0.5" RadiusY="0.5">
                      <GradientStop Color="Azure" Offset="0.1" />
                      <GradientStop Color="CornflowerBlue" Offset="1.1" />
                    </RadialGradientBrush>
                  </Ellipse.Fill>
               </Ellipse>
              </Grid>
               <StackPanel >
                 <ItemsPresenter Margin="2,0,0,0"/>
               </StackPanel>
             </StackPanel>
            </ControlTemplate>
           </ItemsControl.Template>
</ItemsControl>