Preheat oven to 325°F. Grease a 6-well heart baking pan.

In a small heatproof bowl, combine chocolate and butter. Set over but not touching simmering water in a small saucepan and melt, stirring occasionally, until smooth and blended. Set aside to cool slightly.

In a small bowl, stir together flour, baking powder and salt. In another bowl, whisk together egg, sugar and vanilla until doubled in volume. Whisk in chocolate mixture and then flour mixture until just combined. Stir in dried cherries.

Divide batter between wells of prepared pan and smooth tops. Bake until a toothpick inserted into the center of a muffin comes out with a few moist crumbs attached, about 20 min. Transfer pan to a wire rack and let cool 5 min. Remove muffins from pan and set on rack. Serve warm.