Preheat oven to 350°F (175°C). Line a baking sheet with parchment paper or a silicone mat.
Melt chocolate chips and butter together in a microwave or double boiler until smooth; let cool slightly.
In a mixing bowl, whisk eggs, sugar, and vanilla until light and fluffy.
Gradually stir in melted chocolate mixture.
Sift together flour, cocoa powder, baking powder, and salt; fold into wet mixture until just combined.
Scoop cookie dough into balls (about 2 tablespoons each) and place them on the prepared baking sheet.
Optional: Press a few extra chocolate chips into the tops.
Bake for 10–12 minutes until edges are firm but centers are soft.
Allow cookies to cool for 5 minutes on the baking sheet, then transfer to a cooling rack.
Dust with powdered sugar if desired and serve warm.