The brownie recipe is the same one for white chocolate chip cookies
so I’m reproducing here the exact same procedure up until the part when the batter is completely mixed.
Chop the unsweetened chocolate, place in a bowl with the butter, then place the bowl over simmering water. Allow the chocolate and butter to melt, stirring after a minute.
Make sure that there are no lumps before you remove the bowl from the water. Cool the chocolate mixture while you do the other steps.
Preheat the oven to 350F.
In a bowl, stir together the flour, baking powder and salt.
In a large bowl, crack the eggs and add the sugar. Add the instant coffee granules too. Pour in the vanilla extract. Beat everything together for 10 minutes over high speed. The lengthy mixing is to incorporate as much air into the mixture as possible. With a stand mixer, 11 to 13 minutes is no problem but with a hand mixer, well, I had to make some adjustments.
By the end of 10 minutes, the mixture will be quite thick. Pour in the melted chocolate and butter, scraping the bowl to make sure you get all the chocolatey goodness in. Stir a few times by hand then let the mixer do the rest of the work. Two minutes over high speed should be just enough.
Fold the flour mixture into the chocolate mixture — carefully so as not to break the precious air bubbles — until smooth.
Line a 9"x6" cake pan with non-stick baking paper. Leave overhangs on the long sides so that you can lift the uncut baked brownies later.
Prepare the topping by beating the softened cream cheese and sugar until light and smooth. Add the egg and continue beating until well incorporated and the mixture is smooth.
Drop the cream cheese mixture by heaping tablespoonfuls on top of the brownie batter. With a thin blunt knife or a narrow rubber spatula (I used the latter), make the marble patterns by cutting across the mixture. To be more illustrative, imagine that the knife or spatula is your car and the length of the baking pan is the road. Plow through the brownie mix by running the knife or spatula along the length of the batter. When you’re half an inch from the opposite end, make a U-Turn about two inches to your left (or right, depending on which side of the pan you started), and run the knife or spatula again to the other end. Make a U-Turn once more, go the opposite direction again, and so on, and so forth, until you have plowed through the entire length and breadth of the batter.
Bake the cheesecake brownies for 45 minutes in a preheated 350F oven.
That's how it should look when it comes out. Cool in the pan for a few hours. Better still, chill in the fridge after it has cooled to room temperature. If you attempt to lift it out while warm, the thing might crack in places.
When it has cooled, lift out of the pan by holding the wax paper.
Cut into squares, rinsing and wiping the knife after each cut in case some of the chocolate goodness sticks.
You can serve them at this point, with coffee or tea. I placed them in paper cups because my younger daughter was bringing them to school for a potluck lunch as part of the school’s foundation anniversary celebration.
The brownies keep well for several days inside a tightly covered container in the freezer.