Heat the cumin and chili powder in vegetable oil for 30-60 seconds before adding other ingredients to unlock their essential oils and deepen the sauce's complex flavor profile.

Cook tomato paste in the oil for 2-3 minutes before adding broth to develop a rich, slightly sweet undertone that elevates the entire sauce's depth.

Add vinegar gradually at the end and taste as you go—it brightens the sauce and balances richness, but a little goes a long way to avoid overpowering other flavors.

Whisk flour into the oil before adding spices to create a smooth roux, which prevents lumps and creates a silky, restaurant-quality sauce texture.

Let the sauce simmer gently for 15-20 minutes rather than a hard boil—this allows flavors to meld naturally and prevents the sauce from becoming overly reduced or bitter.