Pre-heat the oven to 350ºF.

Grease a 9-inch x 13-inch baking pan with butter. Line with parchment paper, letting the sides of the parchment paper fall over the sides of the pan. Grease the parchment paper as well.

Combine the cocoa powder, flour and salt in a bowl.

Melt the butter and while the butter is still very hot, add the granulated and powdered sugars and beat well. Add the eggs and beat with an electric hand mixer for several minutes – until the mixture is light in color and the beaters leave a distinct path in the batter.

Mix the dry ingredients into the wet ingredients, stirring on until combined. Fold in the chocolate chips. Pour the batter into the prepared baking pan and scatter the raspberries evenly over the pan. Press the raspberries into the batter with your finger.

Transfer the pan to the oven and bake at ˚F for 25 minutes.

While cake cools, make chocolate glaze by melting two thirds the bittersweet chocolate in a double boiler or carefully in the microwave. When it has fully melted but is still very warm, add the remaining third of chocolate and stir until melted. Stir in the oil until completely smooth. Pour the chocolate over the brownies and smooth out with an offset spatula. Bang the pan on the counter to get the chocolate perfectly even. Let the chocolate topping set up in the refrigerator for a couple of hours.

Make the raspberry icing by pressing the raspberries through a fine strainer to remove the seeds, leaving only puréed raspberries. Add the powdered sugar and beat well with a whisk. Thin with a little water if necessary, or thicken with a little more sugar. Drizzle the raspberry icing in a zigzag motion over the brownies.

Let the brownies come to room temperature before cutting into 15 large brownies, or smaller brownie bites.