When a spoonful of just one ingredient lends amazing depth to a dish, it becomes a secret weapon in your culinary arsenal. Achiote paste is just such an item: A Mexican blend of annatto seed, oregano, nutmeg, cinnamon, garlic, and vinegar, it lends smoky, tart, and musky notes that make simple dishes sublime. Work a teaspoon or two into marinades or spice rubs for grilled meats, or stir it into rice cooking liquid. It's also a key component in a killer bowl of beef chili. Find it at Latin markets.