Are you looking for a good ole thigh burning, steady grind up to a short and easy scramble with amazing views with peace and solitude and one where you can bring your dog?  If so, this is the trail for you!  
Start out by heading down the Icicle Road out of Leavenworth, nearly to the end of the road.  Right before Horse Camp is the Jack Pine Trail.  Jump on that for a very short distance, taking a left where the Horse Camp Trail intersects.  Next spur take the right to the Blackjack Ridge trail.  Follow this steep trail (1000' per mile) for about 3 miles.  There are a few blow downs, but all are easy to step over.  After about 3000' you will break out of the forest and see Bootjack Mountain in the distance - a rocky pyramid shaped peak.  Follow the ridge, and then round the corner.  The trail where you round the corner is not so pronounced, so if you start descending, you are on the wrong path and heading down the Snowall Cradle Lake Trail that ultimately will meet up with the French Creek Trail in another 12 mi.  
After rounding the corner at the ridge, continue gaining elevation, picking your way towards the summit.  There is a trail to follow, albeit difficult to see at times, so if you get off track do not worry, just keep heading towards the summit and stay on the outer edge of the treed area.  Once at the base of the summit it is an easy scramble to the top, 6789'.  If you are feeling extra ambitious, you can head to Highchair Mt at just over 7000', tacking on another couple of hours.  
The views from the summit of Bootjack are amazing.  On a clear day, which I had, you can see all the way to Mt Baker, Glacier Peak will be prominent as will Icicle Ridge, Mt Rainier and Mt Stuart-Enchantments. More than likely you will have the summit all to yourself as I only saw 2 people the entire day.
Once back down from your hike, there is an amazing IPA back in Leavenworth at the Icicle Brewery, properly named Bootjack IPA.