Pumpkin pie spice is a blend of spices used when preparing pumpkin desserts (most obviously pumpkin pie) or any variety of harvest dishes. You can buy it at the grocery store or make it at home yourself.
Typically the mix is some blend of cinnamon, nutmeg, ginger, allspice, and sometimes clove and mace. The most common ratio is probably 3 parts cinnamon, 2 parts ginger, and 1 part of any others.
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