This is arguably the easiest way up Dorado Needle. The route was originally established in 1940 by Lloyd Anderson, Karl Boyer, and Tom Gordon. It leads up relatively easy fifth class rock and offers some good exposure. Once up, take in the views of Eldorado Peak, Mount Baker, and the other beauties of the North Cascades.
The Cascade River Road/Eldorado Creek approach is described on the main page.
From Selected Climbs in the Cascades Volume II
: From the large flat portion of Eldorado Glacier at 7,600 feet, just below the base of Eldorado Peak's east ridge at 7,800 feet, begin traversing north, than east, contouring around Eldorado and onto the main body of the Inspiration Glacier. Dean's Spire, the first in a series of small rock summits encountered along the way, marks the route toward a glacier pass (8,200 feet) 1 mile north of Eldorado’s east ridge that leads northwest to the McAllister Glacier. From the pass, traverse left (west) until you are able to descend to a flat area on the glacier at 7,600 feet (Dorado Needle-Eldorado col).
Ascend the steep (30-degree) glacier above the flat, heading northwest to a point high on Dorado Needle itself – to the top of the glacier below several gendarmes on the northwest ridge. Explore the vicinity to find a safe moat crossing, and climb a short rock pitch (low fifth class) to the ridge crest proper. This part of the climb can hold snow late in the season, so you may have detours around snow patches on the rock. On the ridge, two more short but very enjoyable pitches of low-fifth-class climbing on solid rock lead to the exposed summit.
Down-climb the ridge until you are able to make a rappel to the glacier, and retrace the approach route.
Small rack to 2.5 inches
6 feet of webbing for rappel anchor (replace and remove old/worn webbing)