Preheat the oven to 350F (180C or 170C on a convection oven). Line an 8x8 inch (20x20 cm) pan with parchment paper so that there's an overhang around the edges. Alternatively, lightly grease the pan.
In a medium bowl, whisk together the flour, cocoa, ginger, cinnamon, nutmeg, cloves and salt. Set aside.
In a second bowl, whisk together the brown sugar, granulated sugar, eggs, molasses and vanilla extract until you no longer see pieces of egg and there are no longer lumps of brown sugar. Set aside.
In a third large bowl add the butter and chopped chocolate. Melt together on a low heat using a double boiler (be sure the water doesn't touch the bottom of the bowl) or in the microwave. If microwave, use short 45-second intervals on medium power (not high, which is often the default) and stir between each interval until smooth. Let the mixture cool slightly.
Whisk the molasses mixture into the chocolate mixture. Whisk until the mixture looks even.
Carefully fold the flour mixture into the chocolate and molasses mixture. I do this by hand.
Fold in the chocolate chips.
Spoon the batter into the prepared pan and smooth the top.
Bake in the preheated oven for 35-40 minutes, or until an inserted toothpick comes out with a few damp crumbs.
Cool the brownies in the pan until they're completely cooled (the pan shouldn't feel warm). This will take a few hours.
To slice, lift the brownies out of the pan using the overhang of the parchment paper and place on a cutting board to slice (they must be completely cooled). Or if you greased the pan and didn't line it, slice them in the pan.