Bring a pot of water to a simmer. Set a heat-safe bowl over the water, ensuring the bottom does not touch the water. The steam will melt the butter and chocolate.

Add the unsalted butter and semisweet chocolate chips to the heat-safe bowl. With the heat on low, use a rubber spatula to stir the chocolate until it is melted and smooth. This takes about 5 minutes.

In the bowl of a stand mixer fitted with the paddle attachment, add the eggs and 1 ½ cups of the granulated sugar (reserve ½ cup for rolling). Beat on medium speed until combined.

Add in the vanilla extract and the melted butter-chocolate mixture, and beat until combined, stopping to scrape the sides of the bowl as needed.

Add in the all-purpose flour and baking powder, and mix until just combined.

Roll portions of the dough, about 1.5 inches in diameter, in the reserved granulated sugar. Bake according to your preferred method.

After baking, while still warm, press the milk chocolate chips into the tops of the cookies for extra melty goodness.