Tried to update sp-pnp-js, now web part won't run

I tried to update the packages in my project with npm update, but now when I try to gulp serve, it's not finding sp-pnp-js:

gulp no longer finds the library

I tried clearing the cache and then running npm to install the library again, but now all I see is:

What the heck is an ENOENT?

Does anyone know how I can clean up this mess and get my web part compiling again?  It was working just fine until I tried to update the sp-pnp-js library!  :-S