Start black thread on the size 12 1XL dry fly hook and wrap back to about the start of the bend.
Choose a golden pheasant tippet feather sized so both black bars show. Grip the tips, reach in and snip eight to twelve fibres off so the tips stay aligned, then bind them in as the tail and check the length.
Strip a little fibre off the end of the small black chenille so you are catching in the bare thread core - that keeps a lump from forming at the back - and bind it in. Park the thread well up front: you still need room for a Trude wing and a hackle.
Wrap the chenille body forward and catch it in at the front. An extra wrap over the last one gives a thicker thorax if you want it.
Stack a small tuft of white calf tail and measure it about a body length. Spin the thread clockwise to cord it up for a tighter bite, then take two or three tight wraps to set the wing Trude style, flat over the body.
Lift the wing, take one wrap under it, back over the hook, and under again - that puts a collar of thread around the wing butts.
Snip the butts and smooth the taper out, leaving the thread just in front of the wing.
Bind in a brown dry fly hackle sized about one to one and a half hook gaps.
Wrap the hackle fairly heavily - a good five turns. The chenille body has no buoyancy, so this hackle is the only thing keeping the fly on the surface. Tie off and snip.
Take a few more wraps to tighten the head up, whip finish, and check that a tippet still passes through the eye.