Preheat the oven to 350 degrees F (175 degrees C). Grease a 10-inch cake pan.

Melt chocolate chips and butter over a double boiler. Let cool slightly and fold in eggs. Pour batter into the prepared pan. Place pan in a deep roasting pan and pour in enough boiling water to come 1 inch up the sides of the cake pan.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 45 minutes. Let cool 10 minutes and cover with a paper towel.

Turn cake out of pan upside-down onto a cake plate.

Combine raspberries, water, and sugar in a saucepan and bring to a boil. Reduce heat to a simmer and cook until sauce has thickened and reduced, 5 to 7 minutes. Strain sauce and let cool 10 minutes before serving with the cake.