Heat oven to 250. Cover a baking sheet with tinfoil. Put chocolate on the baking sheet and and place it in the oven. Every 5 minutes check on the chocolate and smear/mix it around the sheet with a heatproof spatula. It will slowly turn a light golden colour. Watch it carefully to ensure it doesn't get too dark and remember that the chocolate can burn if it's stuck in one spot.
It may appear seized or crumbly but don't panic. Keep stirring occasionally; it should relax again and get smooth. Even if it's slightly grainy when it's done, that's fine. It will still be great when you add it to your baking.
Financiers (adapted from canelle et vanille)
Combine sugar, flour almond meal and vanilla in a mixing bowl. Add egg whites and stir to combine. Stir in butter, cover bowl with plastic wrap and age in the fridge overnight, or for at least 3 hours.
Mix chocolate into batter. Generously grease financier tins or muffin tins. Fill with batter; only about 1/2 inch high if you are using muffin tins, up to the brim if you are using financier tins. Push one or two raspberries a little ways into the batter-try not to let it sink all the way to the bottom of the tin. This can make it harder to remove the financiers in one piece.
Bake at 375 for about ten minutes, until the centres are set and the edges are browned. For some reason, the ones I made in rectangular tins came out best when I cooled them and the round ones from muffin tins came out best when they were still hot, but ripped apart if I let them cool first. This might involve some trial and error for you. Just eat the ones you ruin and no one will ever know.