1) Preheat the oven to 350°F. Lightly grease (or line with parchment) two baking sheets.
2) Beat together the shortening, butter, oil, and brown sugar until smooth.
3) Beat in the egg, then the yogurt or sour cream, and the vanilla.
4) Add the flour, baking soda, salt, cinnamon, and nutmeg, stirring to combine.
5) Stir in the oats and raisins.
6) Drop the dough in 1 1/2" balls onto the prepared baking sheets; a tablespoon cookie scoop works well here. Leave about 2" between the cookies; they'll spread as they bake.
7) Bake the cookies for 11 to 14 minutes, until they're a medium golden brown in color. Remove them from the oven, and cool right on the pan until they're sturdy enough to loosen with a spatula without breaking. Gently lift each cookie off the sheet with a spatula, and transfer to a rack to cool.
8) Store cookies well wrapped at room temperature for up to a week or so; they'll stay nice and moist. Freeze for longer storage.
Yield: about 3 dozen 3" cookies.