Pre-heat the oven to 375F. Grease your desired cake-pan, muffin tin or small ramekins, with butter, then flour, shaking out the excess. This allows the cake to cook to a crispy consistency, but also slips easily from the pan.
Sift together flour and baking powder.
Simmer in a sauce pot, the cherries and the half-cup of the sugar and vanilla, then puree it with a submersion blender or mash it up with a potato masher. Strain for a smooth batter, or don’t for bits of cherries in the final product.
Melt the chocolate and butter together in a small pot on low heat.
Stir half the flour into the chocolate and butter.
Beat together the eggs and the 1 ½ cup of sugar in a separate bowl.
Mix the butter/chocolate/flour into the eggs.
Combine everything else into the batter bowl in stages, alternating between wet and dry until all the jam, milk and flour is completely used up.
Pour the batter into the greased pan and bake for 40 minutes, or until a toothpick can be pushed into the centre and it comes out clean.