1. Preheat oven to 425 °. In a microwavable glass bowl, melt chocolate and butter on high for about 2 minutes, stirring every 15 seconds. Remove when there are a few lumps of chocolate left; stir until fully melted.
2. Crack the eggs into a separate bowl, add 1/4 cup sugar and beat with mixer on high until triple in volume and soft peaks form, about 5 minutes.
3. Using a spatula fold half the eggs into the chocolate until almost incorporated.
4. Fold in the rest of he eggs until just blended. Make sure you lift the heavier mixture up from the bottom of the bowl.
5. Stir in liquor until blended. Scrape into the springform pan and smooth surface.
6. Bake 15 minutes. The cake will look soft, but it's supposed to.
7. Let cool on rack 45 min. then cover with plastic and refrigerate at least 3 hours. Keeps in refrigerator up to 2 weeks.
1. Still in their bags, thaw raspberries for several hours.
2. Puree using a food processor and strain through a sieve. Add sugar to taste; stir until dissolved.
3. Stir in liquor and lemon juice.
1. Run spatula around the cake and release the sides of the pan.
2. Slice thin wedges and drizzle with raspberry sauce.