This sketch, made by Mithril Arrowand first appeared in the Legolas in Chains Yahoo! group. It made me think of Legolas' first encounter with Rusciphant and Erestor in the forest, and below is the passage that seems to fit!

"At last he composed himself with a loud sigh and turned to confront them.  His face was deadly pale and the dark stain of ire still upon his cheeks looked livid.  He stared coldly from one to the other of them, and in spite of himself Rusciphant stepped back and dropped his head in shame, for there was more there than anger in the gleaming azure eyes.

Legolas walked quietly back to them and stood with arms crossed before his chest, then slowly unfolded them and let them drop, tight fisted, to his sides.  He waited, never letting his attention wander from Rusciphant, and finally that elf could stand the wordless recrimination no longer and faced him."

Mael Nuin Daedelu [Lust Under the Canopy]