How do I make pandoc add a package to my header when transpiling Markdown to LATeX?

Question

I have a Markdown file that I want to compile to LaTeX. I want to put \usepackage{tikz} in the header. Here's what I tried:

$ cat test.md | pandoc -s -f markdown -t latex -H \usepackage{tikz} > test.tex
File usepackage{tikz} not found in resource path

Then I removed the -H flag and made a YAML header for my Markdown.

---
title: My title
author: My name
header-includes:
  - '`\usepackage{tikz}`{=latex}'
---

It yields

File tikz not found in resource path.

I'm using Tectonic so I don't have TikZ installed locally. I just want to add a string of text to my header, so I guess I must be on the wrong path if pandoc expects to find software in some path.

How do I make pandoc add a package to my header?

Answer 1

The comment of Fran did the trick.

Instead of:

  - '`\usepackage{tikz}`{=latex}'

I had to use

  - \usepackage{tikz}

and make sure that pandoc is called without -H \usepackage{tikz}.