cancel line through a tikz picture in the background

I have defined a command \kr to draw a small circle to use it as a letter. Later I want to cancel out a circle. But the cancel line is in the background, see picture. How can I make the cancel line be in the foreground?

Code:

\documentclass{beamer}
\usepackage{tikz}
\usepackage{cancel}
\newcommand*\kr[1]{%
\begin{tikzpicture}[baseline=(C.base),inner sep=0pt,minimum size=0pt]
\node (C) {\phantom{a}};
\node[fill=#1!50,draw,circle,minimum size=0.3cm] (C.center) {};
\end{tikzpicture}}

\begin{document}
\kr{green} \cancel{\kr{green}}
\end{document}

• draw a line over the node instead of cancel? – percusse Nov 3 '15 at 16:38

Maybe something like that:

\documentclass{beamer}
\usepackage{tikz}
\usepackage{cancel}
\newcommand*\kr[1]{%
\begin{tikzpicture}[baseline=(C.base),inner sep=0pt,minimum size=0pt]
\node (C) {\phantom{a}};
\node[fill=#1!50,draw,circle,minimum size=0.3cm] (C.center) {};
\end{tikzpicture}}

\newcommand*\mycancel[1]{\makebox{\rlap{#1}\cancel{\phantom{#1}}}}

\begin{document}
\kr{green} \mycancel{\kr{green}}
\end{document}