Seat the 4.6mm copper slotted bead at the jig eye, add eight to ten wraps of.015 wire behind it and shove them into the back of the bead. Loading the weight right at the front is what makes this fly dive nose-down on the pause.
Cover the wire with olive 140D and run the thread back to the bend, then tie in a clump of olive mini marabou about a shank and a half long, keeping the tie-in point tight and short.
Dub a shaggy dark olive UV peacock flash body from the bend forward to the 65% mark, brushing it out as you go so it merges into the marabou rather than stopping at a hard line.
Spin the olive CDC dubbing into a loose loop and wrap two or three turns from the 65% mark to the bead, then brush the collar out hard. CDC dubbing traps air and pulses in a way plain synthetic dubbing does not, which is what gives this simple fly its life.
Sweep the collar fibers back over the body with a few thread wraps and whip finish behind the bead.
Coat only the thread wraps behind the bead with Bone Dry, leaving the dubbing and marabou completely dry.
Other versions
3 more in the app: Reference Recipe, Fly Fish Food Tie, variant 1, Fly Fish Food Tie, variant 2.