Step 1: Preheat your oven to 350°F (175°C). Line two baking sheets with parchment paper.
Step 2: In a large bowl, cream together the softened butter, granulated sugar, and light brown sugar with an electric mixer until light and fluffy, about 2-3 minutes.
Step 3: Beat in the eggs one at a time, incorporating each fully before adding the next. Stir in the vanilla extract.
Step 4: In a separate medium bowl, whisk together the all-purpose flour, unsweetened cocoa powder, baking soda, and salt.
Step 5: Gradually add the dry ingredients to the wet ingredients, mixing on low speed until just combined. Be careful not to overmix the dough.
Step 6: Gently fold in the chocolate chips (or chunks) and then carefully fold in the fresh or frozen raspberries. Mix just enough to distribute them without crushing the berries too much.
Step 7: Drop rounded tablespoons of dough onto the prepared baking sheets, leaving about 2 inches between cookies.
Step 8: Bake for 10-12 minutes, or until the edges are set but the centers still look slightly soft and fudgy. Do not overbake!
Step 9: Remove from the oven and let the cookies cool on the baking sheets for 5 minutes before transferring them to a wire rack to cool completely.
Step 10: Enjoy your perfectly fudgy chocolate raspberry cookies!