如何填充SolidColorBrush /椭圆

Question

<Ellipse HorizontalAlignment="Left" VerticalAlignment="Top" Width="48" Height="48" RenderTransformOrigin="-0.014,0.003" Margin="0,0,104,5">               
    <Ellipse.Fill>
        <SolidColorBrush Color="#683FB0"></SolidColorBrush>
    </Ellipse.Fill>  
</Ellipse>

在该彩色圆圈内，我想添加一个icon / textblock等。