Preheat oven to 350 degrees, rack in the middle position.
Line a 12-cup muffin pan with double cupcake papers. This recipe makes 18 cupcakes, so you can add an additional 6-cup muffin pan or you can butter and flour an 8-inch square cake pan.
Microwave the chocolate, raspberry syrup and 1/4 cup sugar in a microwave safe bowl on high for 1 minute. Stir. Microwave again for another minute. At this point, the chocolate will be almost melted, but will retain its shape. Stir the mixture until smooth and let cool to lukewarm.
Measure flour, mix in baking powder and salt, and set aside. In an electric mixer beat the butter and 1 1/2 cups sugar until light and fluffy, about 3 minutes.
Add eggs, one at a time, beating after each addition to make sure they're thoroughly incorporated. Add approximately 1/3 of the flour mixture and 1/3 of the milk. When that's all mixed in, add another third of the flour and 1/3 of the milk. Once incorporated, add the remaining flour and milk. Mix thoroughly.
Test your chocolate mixture to be sure it's cool enough to add (don't cook the eggs!). If it's fairly warm to the touch but not so hot you have to pull your hand away, you can add it. Stir thoroughly.
LET THE BATTER REST FOR 5 MINUTES. Then stir it again by hand and fill each cupcake paper 3/4 full. (If you decide to use the cake pan, fill it as well.).
Bake the cupcakes for 20-25 minutes. (The 8-inch cake pan should bake an additional 5 minutes.).
You can use a double boiler, or a saucepan on the stovetop, stirring CONSTANTLY.
Put the chocolate chips in the pan/boiler over medium heat. Stir until chocolate chips are melted. Stir in sweetened condensed milk and cook approximately 2 minutes, stirring constantly until the frosting is shiny and of spreading consistency.
Spread on cupcakes, make sure to fill the "frosting pocket.".
Give the frosting pan to your favorite person to scrape.
(The cupcakes are better if you cool and cover them for a few hours before frosting them.).