Pulse 1 1/2 cups raspberries in a blender or food processor until reduced to a powder.

Put white sugar, cocoa powder, oil, baking powder, vanilla, salt, and 1/4 cup powdered raspberries in a large bowl. Beat together with a mixer until well blended. Mix in eggs 1 at a time, waiting until each addition is incorporated before adding the next. Add flour; mix on low speed until incorporated. Cover with plastic wrap. Chill 4 to 8 hours or overnight.

Preheat oven to 350 degrees F (175 degrees C). Line a baking sheet with a silicone baking mat or parchment paper.

Put confectioners' sugar in a small bowl; put remaining powdered raspberries in another small bowl.

Roll walnut-size pieces of dough into a ball, then roll each ball partly in powdered raspberries and partly in powdered sugar. Arrange on prepared sheet and bake until barely set and crackled on top, 10 to 12 minutes. Cool on sheet 10 minutes. Transfer to a wire rack to cool completely.