Lay ten to twelve wraps of 0.015 lead wire on the nymph hook shank (fewer if using 0.020); the fly is meant to sink.
Start the brown or olive thread, build a dam behind the weight, carry the thread over the wire with securing wraps, build a dam in front, then take the thread back to the start of the bend.
Pull a strand of Antron or Z-lon; it splits into three thinner strands, so use one. Catch it in on top at the bend with a small pinch wrap and a couple of turns; trim or bind down the fluff.
Rotate the hook and tie a second strand on the bottom the same way, laying it off to one side to clear the hook point and binding it back as far as the top strand. Trim the fuzz, bury the ends and level the hook: two distinct strands, top and bottom.
Wax the thread and dub a noodle of the fur and sparkle yarn or Ice Dub mix. Starting where the Antron was caught in, wrap a football-shaped body over the weight, adding more dubbing as needed.
Bring the top Antron strand forward with two loose wraps, then the bottom strand with two loose wraps, keeping them separated. Slip a bodkin under each strand and pull out a little slack so it can be spread around the body, then take a couple of tight wraps.
Before snipping, pull the strands around the body with the bodkin or thumbnails, top and bottom, into a loose veil (it imitates the pupa's air bubble; the body shows through when wet). Pull the ends up and trim them close.
Lay about six Partridge or grouse fiber tips on the far side and six on the near side, about half the body length; check the lengths, tighten and trim the butts.
Flatten the head area with thread. Snip four or five Marabou strands from the base of a feather, snip the tips off, moisten them together, tie in with a loose wrap then tighten. Using hackle pliers, take about two wraps, zigzag the thread through to catch it and snip the excess.
Clean up the head, build the ramp back up, whip finish and add a drop of head cement.
Other versions
2 more in the app: Classic Recipe, Classic Recipe (2).