Faire un joli cadre de texte

 \documentclass{article}
\usepackage{tikz}
\usetikzlibrary{decorations.pathmorphing,calc,shadows.blur,shadings}

\newcounter{mathseed}
\setcounter{mathseed}{6}
\pgfmathsetseed{\arabic{mathseed}} % To have predictable results
% Define a background layer, in which the parchment shape is drawn
\pgfdeclarelayer{background}
\pgfsetlayers{background,main}

% This is the base for the fractal decoration. It takes a random point between the start and end, and
% raises it a random amount, thus transforming a segment into two, connected at that raised point
% This decoration can be applied again to each one of the resulting segments and so on, in a similar
% way of a Koch snowflake.
\pgfdeclaredecoration{irregular fractal line}{init}
{
  \state{init}[width=\pgfdecoratedinputsegmentremainingdistance]
  {
    \pgfpathlineto{\pgfpoint{random*\pgfdecoratedinputsegmentremainingdistance}{(random*\pgfdecorationsegmentamplitude-0.02)*\pgfdecoratedinputsegmentremainingdistance}}
    \pgfpathlineto{\pgfpoint{\pgfdecoratedinputsegmentremainingdistance}{0pt}}
  }
}

% define some styles
\tikzset{
   paper/.style={draw=black, fill=none},
   irregular border/.style={decoration={irregular fractal line, amplitude=0.1},
           decorate,
     },
   ragged border/.style={ decoration={random steps, segment length=2mm, amplitude=1mm},
           decorate,
   }
}

\def\tornpaper#1{%
\tikz{
  \node[inner sep=1em,text width=.85\linewidth,align=flush left] (A) {#1};  % Draw the text of the node
  \begin{pgfonlayer}{background}  % Draw the shape behind
  \draw[paper] % recursively decorate the bottom border
     \pgfextra{\pgfmathsetseed{\arabic{mathseed}}\addtocounter{mathseed}{1}}%
      {decorate[irregular border]{decorate{decorate{decorate{decorate[ragged border]{
        (A.north west) -- (A.north east)
      }}}}}}
      \pgfextra{\pgfmathsetseed{\arabic{mathseed}}}%
            {decorate[irregular border]{decorate{decorate{decorate{decorate[ragged border]{
            -- (A.south east)
            }}}}}}
     \pgfextra{\pgfmathsetseed{\arabic{mathseed}}}%
      {decorate[irregular border]{decorate{decorate{decorate{decorate[ragged border]{
      -- (A.south west)
      }}}}}}
     \pgfextra{\pgfmathsetseed{\arabic{mathseed}}}%
           {decorate[irregular border]{decorate{decorate{decorate{decorate[ragged border]{
           -- (A.north west)
           }}}}}};
  \end{pgfonlayer}
}}

\begin{document}
\tornpaper{%
    {\Large Mon text en large} mon text
}

\end{document}