Toast the cinnamon, coriander, cloves, and quatre-épices in a small skillet over low heat until fragrant.
Finely grind the toasted spices with the black pepper in a spice or coffee grinder. Sift through a fine-mesh strainer, stirring with a spoon. Store in a sealed container at room temperature or in the freezer. (The squab spice begins to lose some of its intensity after a few days; fr