Warm fat, not raw. Curcumin, the compound doing the work in turmeric, is fat-soluble and will not go anywhere in a cold dressing. Warming it in oil pulls the aromatic oils out and rounds off the raw bitterness.
Fresh rhizome over dried powder. Fresh turmeric carries bright ginger and citrus notes with something floral behind them. Dried powder goes dusty and chalky on fresh produce.
The black pepper is not garnish. Piperine in black pepper increases curcumin absorption, and the sharp pungency is the contrast the sweet fruit needs.

