How to get this chapter title format

Question

I'd like my chapters to look like this:

(if it helps, the picture is from the Princeton Lectures in Analysis textbook series by Elias Stein) I know how to insert the quote (using the epigraph package) but I can't find how to style the chapter title like that. I've tried reading the manuals for fncychap and titlesec (I am using the latter already, to make the section titles smaller) but I couldn't understand how to properly use them. Can anyone help me? Thanks!

Here's a MWE so you can make a quick copy-paste to your computer:

\documentclass[12pt,letterpaper]{book}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{titlesec} 
\title{MWE}
\author{nelichu}
\begin{document}
    \chapter{Measure Theory}
\end{document}

Answer 1

Something like this?

\documentclass[12pt,letterpaper]{book}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{titlesec}
\usepackage{newpxtext,newpxmath} % Palatino font
\title{MWE}
\author{nelichu}

\titleformat{\chapter}{\bfseries\Huge}{{\fontsize{60}{72}\selectfont\thechapter}}{1em}{}
%\titleformat{\chapter}{\bfseries\Large}{{\Huge\thechapter}}{1em}{}

\begin{document}
\chapter{Measure Theory}
Normal text.
\end{document}

I have used Palatino font because it looks like TeX's default serif font cannot be arbitrarily increased in size. I have referred to this answer for the same.

If you are okay with smaller chapter font, you can also try to use this instead:

\titleformat{\chapter}{\bfseries\Large}{{\Huge\thechapter}}{1em}{}