I figured it out and am sharing the result here. Most everything was gleaned off the following pages:
https://github.com/chdemko/pandoc-latex-environment
https://github.com/Wandmalfarbe/pandoc-latex-template
To start, I run pandoc in a Docker file, so I needed to download some additional packages in order for this to work. Here is a small selection of the packages I downloaded within my "Dockerfile" and then how I started it up:
FROM pandoc/latex:2.10
#RUN tlmgr option repository http://ctan.math.washington.edu/tex-archive/systems/texlive/tlnet \
RUN tlmgr option repository http://ctan.math.utah.edu/tex-archive/systems/texlive/tlnet \
&& tlmgr update --self \
&& tlmgr install adjustbox awesomebox babel-german background bidi collectbox csquotes
everypage environ etoolbox filehook fontawesome5 footmisc footnotebackref framed fvextra
letltxmacro ly1 mdframed mweights needspace pagecolor pgf sourcecodepro sourcesanspro
tcolorbox titling tools trimspaces ucharcat ulem unicode-math upquote xcolor xecjk xurl
zref
RUN apk --no-cache add \
ghc cabal libc-dev zlib-dev python3 py3-pip
RUN cabal update
#RUN cabal --global --prefix=/usr/local v2-install cabal-install
#RUN cabal --global --bindir=/usr/local/bin v2-install pandoc-include-code-1.4.0.0
#RUN pip3 install pandoc-extract-code pandocfilters
RUN pip3 install pandoc-extract-code pandocfilters pandoc-latex-environment
The key ingredient here was to include all the required packages needed by tcolorbox for eisvogel, i.e. install, tools, xcolor, tcolorbox, etc., and also to download and include pandoc-latex-environment in the statement "RUN pip3 install....."
Next, I needed to add the argument “--filter pandoc-latex-evironment” to my pandooc command. I use a shell script that is already highly customized for my environment, so I simply added an extra line to use the filter "pandoc-latex-environment".
Then I had to add some lines to the Markdown file's preamble:
header-includes:
- |
```{=latex}
\usepackage{tcolorbox}
\newtcolorbox{info-box}{colback=cyan!5!white,arc=0pt,outer arc=0pt,colframe=cyan!60!black}
\newtcolorbox{warning-box}{colback=orange!5!white,arc=0pt,outer arc=0pt,colframe=orange!80!black}
\newtcolorbox{error-box}{colback=red!5!white,arc=0pt,outer arc=0pt,colframe=red!75!black}
And then, while still in the preamble below that, add the following:
pandoc-latex-environment:
tcolorbox: [box]
info-box: [info]
warning-box: [warning]
error-box: [error]
Once the code was in the preamble, I could start adding to the Markdown text itself. Taking examples I gleaned off of various pages here in StackExchange, I added the following:
## Standard Box
\begin{tcolorbox}
\abovedisplayskip=0pt%
\belowdisplayskip=0pt%
%\vspace{-1\baselineskip}
\begin{align}
\sigma & = \beta_{0} \label{eq:Model0} \\
\sigma & = \beta_{0} + \beta_{1}K + \beta_{2}K^2
\label{eq:Model1} \\
\sigma & = \beta_{0} + \beta_{1}K + \beta_{2}K^2 + \beta_{3}(T-t) + \beta_{5}K(T-t)
\label{eq:Model2} \\
\sigma & = \beta_{0} + \beta_{1}K + \beta_{2}K^2 +
\beta_{3}(T-t) + \beta_{4}(T-t)^2 + \beta_{5}K(T-t)
\label{eq:Model3}
\end{align}
\end{tcolorbox}
Then I began customizing the colors of each box:
::: info
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam aliquet libero
quis lectus elementum fermentum.
:::
::: warning
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam aliquet libero
quis lectus elementum fermentum.
:::
::: error
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Nam aliquet libero
quis lectus elementum fermentum.
:::
Now, I am able to get the following image rendered when I convert my Markdown file to a PDF file.

Much thanks to everyone who posted a small portion of the solution here on StackExchange. There were about 5-6 pages I was able to glean partial solutions from.
tcolorbox
: github.com/Wandmalfarbe/pandoc-latex-template/blob/master/…eisvogel
gives you the tools to make a box in markdown, usingtcolorbox
, just look at the examples. Maybe you could clarify, what you want to achieve by providing a minimal working example (MWE)