Preheat oven to 350 degrees F.
Blanch the almonds in boiling water, until the skins peel off.
Melt the butter in a large ovenproof skillet over moderate heat and cook until it turns light brown and smells nutty. Add the almonds and salt and cook, stirring occasionally, over moderate heat until the almonds begin to color, about 5 minutes, coat and toss in the spice mix thoroughly. Transfer the skillet to the oven and bake until the almonds are medium-brown, about 15 minutes.
Remove from the oven, taste for flavor, add more spice mix or salt, if necessary. Return to the oven for another 5 minutes. Transfer the nuts to a sheet pan; they will crisp as they cool. Store the cooled almonds in an airtight container at room temperature. (See Cook's Note)
Toast the fennel seeds, coriander seeds, and peppercorns in a small, heavy pan over medium heat. When the fennel turns light brown, work quickly. Turn on the exhaust fan, add the red pepper flakes, and toss, toss, toss, always under the fan. Immediately turn the spice mixture out onto a plate to cool. Put in a blender with the chili powder, salt, and cinnamon and blend until the spices are evenly ground. If you have a small spice mill or a coffee grinder dedicated to grinding spices, grind only the fennel, coriander, pepper, and chili flakes. Pour into a bowl and toss with the remaining ingredients.
Toasting freshens spices, releases their oils, and makes them more fragrant, as well as adding a new dimension of flavor. Keep the spice mix in a glass jar in a cool, dry place, or freeze.
Taste your chili powder and, if too spicy and hot, cut back the amount. California chiles are almost sweet, not hot.
Chop these nuts and add them to a turkey stuffing or a rice pilaf.