The approach is super easy. I went around the left side of the lake (passing under the Aprons) and personally think it's a better call to go around the right side of the lake. Supposedly there's a faint trail that's fairly easy to follow. The couloir itself is straightforward. Sticking to the left generally seemed to be the easiest option, although staying right and then traversing over as needed might work well too. I used my ice tools on this route, it's not super steep but it's steep enough that I found it to be incredibly helpful to be able to just make those bomber stick in the snow. I think it took me a total of 45 minutes to get from the parking lot to the top of the couloir. From there I highly recommend thrashing Spalding real quick, then hitting West Evans before nailing Evans. The best part is the downclimb is a ride back down with a tourist! If you prefer to walk down, which I opted for, take the East Face route down. It's quick and easy. Climb on!
Easy approach and quick climb from Summit lake.