Inserting images of a given text width in Pandoc Markdown to Beamer

I want to include images in my beamer slides via Pandoc's conversion from Markdown sometimes without using the regular ![]() image inclusions (which introduces Figures).

This is accomplished by using a LaTeX region with \includegraphics, with the width attribute set to some multiplier applied to \textwidth, like so:

## Some title

Some text

\begin{center}
    \includegraphics[width=0.3\textwidth]{./test.jpeg}
\end{center}

Example output: