@ClimbEveryMount Camping near Aspen? That's like asking Where can I fish in the Florida Keys?
I just peeked at the Caltopo.com Mapbuildertopo overlay (https://caltopo.com/m/KJ9G) from my last Maroon Bells 4 Pass Loop trip (3 times, love that route!), because I was too lazy to walk across my man-cave to get my White River/Maroon Bells Wilderness topo map...and see probably hundreds of miles of wilderness trails where one can camp.
Since you've been to Maroon Bells, assuming the trailhead at the MB Lake TH, there are several campsites along the road in. Reservations needed. Indeed, reservations are needed at almost all of the campgrounds.
But anyway, thanks for giving me an excuse to post photos!