1. Heat the oven to 350 degrees and lightly grease a 12-cup muffin pan. In a fairly deep bowl (because the mamey might end up flying everywhere), lightly mash mamey with a fork until it’s mostly smooth. Personally, I like a little bit of mamey lumpiness.
2. In a medium bowl, cream the butter and sugars with an electric hand mixer until light and fluffy, about 3 minutes.
3. In yet another medium bowl — sorry if you’re washing dishes later — whisk together the flour, whole-wheat flour, baking powder, baking soda, salt, cinnamon, ginger and allspice. Grab another medium bowl and whisk together the yogurt, egg and vanilla.
4. Scrape down the sides of the butter bowl and alternately add the dry and wet ingredients. Do not overmix. Gently and lovingly fold in the mamey. Snag a taste with a spoon, just to make sure it’s headed in the right direction.
6. Using an ice cream scoop (about one-half cup capacity), scoop the batter into each muffin cup. Bake for 35 to 40 minutes, or until toothpick inserted into muffin center comes out clean. Mine ended up being closer to 35.
The Mija Chronicles