Watching the laravel videos here I'd expect would be beneficial.
You may want to use the full framework too, caters for using for api usage too. Have a look at a laravel official package for api auth - https://laravel.com/docs/5.5/passport
Laravel is pretty quick as it is (especially since php7). Lumen is kinda like Laravel stripped back which may lead to frustration when you'd like to use some basic niceties of Laravel which isn't in Lumen, or disabled by default, e.g. Eloquent
All the learning material is geared towards Laravel, you'll have a better time getting up to speed.